Journal of the Radio Society of Great Britain 4111F CATRO NICS FOR NO» 'T RI O GET READY FOR THE NEW BANDS WITH A TRIO TRANS MITTER

L_ t e S 30S R2400 WITH NEW BANDS WITH NEW BANDS 2M SYNTHESIZED PORTABLE

TR2400 Brief Specification TS130S Brief Specification Frequency Range: 144-148MHz TS830S Brief Specification Frequency Range: 8 bands, 80m-10m Mode: FM Frequency Range: 9 bands. 160m 10m Modes: CW, USB, LSB RF Output Power: 1.5 watts min. Modes: CW, USB, LSB Final Power Input: ...203 watts PEP ISSF. Sensitivity: 1.0e for 30dB SIN Final Power Input: 220 watts PEP (SSA , ..,150 watts DC ICW Display: LCD 180 watts DC ICW) RX Sensitivity: 0'25V at 10dB S/N Memories: 10 built in RX Sensitivity: 0/25uV at 10dB S/61 Commies' Price. £491 Scanning: Auto in 5kHz steps Catronics Price: £639 25W PEP version also available TS130V at £401 Catronics' Price: £198

TS778 WELCO ME TO ViDe000 ALL MODE 2M +70C M 2M COMPACT ALL MODE - • "

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TS770 Brief Specification Frequency Range: 144 146MHz TR9000 Brief Specification 144 I48MHz 430-440MHz Frequency Range: Modes: USB, LSB. FM. CW Mode: SS8 (USB, LSE!). CW, FM 10 watts RF Output Power: 10 watts. Only for FM: RF Output Power: Sensitivity: SSEUC W 0.25/4V for 10dB S/N 10W (Hi)/Approx. 1W ILOWI FM 0.250V for 12dB SINAD Sensitivity SSB/C W 0-5uV for 10dB Digital, phase locked VCO Ni/N Frequency Control: 5 built in FM 1/4V for 30dB + NI ife Memories: CATRONICS Auto-- 25/ 12.5kHz1100Hz 20dB quieting 1FM) Less than 0-4uV Scanning: Catronics' Price: £345 CatiOrliCS . Price. E730

L_ H7800 to.Lïki 840 G MOCDO 2M FM SYNTHESISED 70cm FM SYNTHESISED MOBILE COM MUN -CATI • NS RECEIVER

TR7800 Brief Specification R1000 Brief Specification Frequency Range: 144-145/995MHz TR8400 Brief Specification Frequency Range: 200kHz 30MHz RF Output power: HI 25W, LO 5W (adjustable) Frequency Rango: 430-439/975MHz Modes: AM. USB, 1.56, CW RX sensitivity: 0.20V for 12dB SINAI) Channel Spacing: 25kHz Sensitivity <2MHz: 5/4V Autoscan: 5kHz or 25kHz RF Output Power: 10W 1H11 or 1W ILOI >2MHz: 0-50/ Memories: 15 inc Ix priority RX Sensitivity: 0/4r1V for 12dB SINAI) for tfide S r N/N on SSB Repeater shift: • I - 600kHz Et Reverse Memories: 5 (scanningl Digital Readout: to IkHz Frequency display: 4 digit LED & Mom. No. Repeater shift: t.1.6kHz Clock: Quartz controlled Catrontes Price: £2613 Catronics' Price: f279 Catronics' Price C2B5

We always have a good selection of used equipment in stock—ask for current list. We ale 300 yards from Wallington Railway Station i London Bridge or Victoria! Frequent buses !morn Croydon and Sutton Three large APPROVED .% car parks within 100 yards Hire purchase facilities available on all equipment. Credit cards accepted. Mail orders normally dealt with on day of receipt Securicor delivery arranged All pr.cos Include VA -I- it I,C) CATRONICS LTD, DEPT 106, COM MUNICATIONS HOUSE 20 WALLINGTON SQUARE, WALLINGTON, SURREY SM6 8RG. Tel: 01-669 6700.

Shop showroom open Monday Friday: 9.00 5.30, closed for lunch: 12.45 1.45. Saturdays: 9.00 1.00. EXPORT SALES WELCO ME—PAY BY CREDIT CARD OR BANKERS CHEQUE JUNE 1981

VOLUME 57 No 6 CO W u ication

EDITOR CONTENTS A. W. Hutchinson 517 Peter Balestrini, G3BPT—ohituary QTC Editorial assistant Election of regional and area representatives

Miss S. M. Walker 518 The RX80 (Part 5)—A. L. Bailey, G3VVP 0

521 New products — Thandar SC110 oscilloscope. Thandar TG 100. Thandar TF040 bench Draughtsman frequency meter D. E. Cole 522 Equipment review—Drake TR7 hf transceiver—P. A. Barron, BSc, G3WTM, and P. I. Hart, BSc. G3SIX Editorial secretary 525 New products— Thandar PKW -5000 eprom programmer. Thandar TM354 led. Mrs J. D. Brown hand -held multimeter

526 A vlf up-converter for shortwave receivers—R. Lapthorn, BEng, G3XBM Contributions lincluding Me mbers ads) and all correspondence concerning the content of Radio 527 A simple add-on unit for counting audio frequencies—). Braithwaite. G4COL Communication should be addressed to: 528 The ten-turn "chopstick" helical: a high gain antenna for satellite work—Colin The Editor, RSGB, Richards, 9M2CR 88 Broomfield Road, Chelmsford, 530 Technical topics — Pat Hawker, G3VA Essex CM1 1SS 536 Microwaves—Charles Suckling, G3WDG Tel 0245 84938 538 4-2-70— lohn Morris, G4ANB Office hours: 0900 to 1700 541 SWL news—Bob Treacher, BRS32525 ADVERTISING 542 The month on the air—John Allaway, C3FK M Advertising, other than Me mbers' ads, should be sent to: 545 Propagation predictions FIF propagation study Mr C. C. Lindsay, 2 Leyburn Gardens, 546 Raynet—G. Cluer, G4AVV Croydon, Surrey CRO 5NL 547 Your opinion

Tel 01-686 5839 (Not RSGB) 548 Contest news Hours: 0915 to 1715 551 Contests calendar Mobile rallies calendar EDITORIAL PANEL Special event station Looking ahead J. P. Hawker, G3VA R. F. Stevens, G2BVN 552 Club news

554 Obituaries

555 Members' ads

Correspondence concerning the distribution of the journal and all other Society matters should be Technical articles on subjects of amateur interest are always welcome and should be sent to: The addressed to: Editor, Radio Communication, 88 Broomfield Road, Chelmsford, Essex CM1 1SS. RSGB Headquarters, All articles received are reviewed for technical merit by the RSGB Technical Et Publications 35 Doughty St, Committee, or an acknowledged expert on the subject, before acceptance. Payment will be made London WC1N 2AE for all articles published. The editor will be pleased to send intending authors a manuscript preparation guide and to give Tel 01-837 8688 any other advice and assistance requested. Office hours: 0915 to 1715

Radio Communication is published by The Radio Society of Great Britain as its official journal on the first Friday of each month and is sent free and post paid to all members of the Society

26,007 copies per Closing date for contributions ABC issue average unless otherwise notified: RADIO SOCIETY OF circulation in 1980 five weeks before publication date GREAT BRITAIN 1981 •:› \ RIo pacesetter in amateur radio

TS - 8 3 0 S V.B.T., notch, IF shift, wide dynamic range The TS-830S has every • Wide receiver dynamic range. • 61469 final with RF negative with 20Hz steps, five conceivable operating feature Junction FETs in the balanced feedback. Runs 220W PEP memories, digital display. built-in for 160-10 metres mixer, MOSFET RF amplifier (SSB)/180W dc (CW) input • AT-230 antenna tuner/SWR (including the three new bands). at low level, and dual on all bands. and power meter/antenna It combines a high dynamic range resonator for each band. • Built-in RF speech processor. switch; 160-10 metres, with variable bandwidth tuning • Variable bandwidth tuning • Narrow/wide filter selection including three new bands. (VBT). IF shift, and an IF notch (VTB). Varies IF filter pass- on CW. • YG-455C (500Hz) and filter, as well as very sharp filters band width. • SSB monitor circuit to check YG-455CN (2WHz) CW filters in the 455kHz second IF. Its • Notch filter (high-O active transmitted audio quality. for 455kHz IF. optional VFO-230 remote digital circuit in 445kHz second IF. • RIT Ireceiver incremental • YK-88C (500Hz) and YK-88CN VFO provides five memories. • IF shift (passband tuning). tuning) and XIT !transmitter (270Hz) CW filters for • Built-in digital display (six incremental tuning). 8.83MHz IF. TS-830S FEATURES: digits, fluorescent tubes), (VFOs for TS-830S, TS-130 • ft_SB, USB and CW on 160-10 analog subdial, and display OPTIONAL ACCESSORIES: Series, and TS-120S are metres, including the new 10, hold )DH) switch. • SP-230 external speaker with compatible with all three 18, and 24MHz bands. • Noise-blanker threshold level selectable audio filters. series of transceivers.) Receives WVVV. control. • VFO-230 external digital VFO TS-830S £39.51 inc VAT. Carriage £4.50.

TS - 1 3 0 S / V processor, N/W switch, IF shift, DEC option The compact, all solid-state 10 metres TS-130V runs 25W • Built-in RF attenuator • MB-103 mobile mounting HF SSB/CW mobile or fixed slam)! PEP/20W dc input on all bands. • IF shift (passband tuning) bracket. TS-130 Series transceiver covers • Built-in speech processsor. • Effective noise blanker • PS-20 base-station power supp) 3.5 to 30MHz, including the three • Narrow/wide filter selection on for TS-130V new bands both CW (5C0Hz or 270Hz) and OPTIONAL ACCESSORIES: SSB 11.8kHz) with optional • PS-30 base-station power Optional DFC-230 Digital TS-130 SERIES FEATURES: filters. supply. Frequency Controller • 80-10 metres, including the new • Automatic selection of side- • YK-88C (530Hz) and Frequency control in 20Hz steps 10, 18. and 24MHz bands band mode (LSB on 40 metres YK-88CN 1270Hz) CW filters. with UP/DOWN microphone Receives WVVV. and below, and USB on 30 • YK-88SN (1-8kHz) narrow SSB supplied with DFC-230) Four • TS-130S runs 2cmv PEP/160W metres and above). SSB filter. memories and digital display. (Also dc input on 113-15 metres and REVERSE switch provided • AT-130 compact antenna tuner operates with TS-120 and 160W PEP/140W dc on 12 and • Built-in digital display (80-10 metres, including three TS-880S.( new bandsl. TS— 130S £491 05 inc VAT • SP-120 external speaker. TS-130S £401.34 inc VAT. • VFO-120 remote VFO. Carriage £4.50.

PS-30 SP-120 TS-130S VFO-120 L O W E ELE C T R O NIC S Ltd CHESTERFIELD ROAD MATLOCK DE4 51E TEL 0629 2430/2817

490 RADIO COMMUNICATION June 1981 PAPPROVEre r i n H I C ) pacesetter in amateur radio -r ni C)

TS 530 Sbuilding on success

BIRMINGHA M Ward Electronics Soho House, 362 364 Soho Rd. Birmingham B21 9QL 021 554 0708 "n.

• f`.. ' BUCKINGHA MSHIRE (t) Photo Accoustics Ltd 58 High St Newport Pagnell ttS,_ Bucks, 0908 610625

Inario••• don ne ••• ' 4 2 "

e •• 'I Ifoe 4e-> j4e. • • EAST SCOTLAND J t* ' r Jay-Cee Electronics 20 Woodside Way L) . 940 ••••••••80 . M M . Glenrothes Fife KY7 5DE. 0592.756962

ESSEX The all new TS -530S is firmly based on the reputa- • All-band coverage including WARC Waters Stanton Electronics • RIT and XIT. tion of the TS -520 series but incorporating many of Warren House the features of the superb TS -830. Now included as • Speech processor. 18 20 Main Rd standard are the following features: • Wide/narrow filter switching. Hockley Essex. 0702 206835

s„eete,.edrivet.ip' LANCASHIRE Stephens-James Ltd 47 Warrington Rd Leigh 0942 676790

NORTH LONDON Radio Shack Ltd 188 Broadhurst Gardens London NW6 3AY TR-9500 the 70 centimetre 9000, built on success 01-624 7174

SOUTH LONDON Catronics Ltd 20 Wallington Square Wallington SM6 8RG 01-669 0700

W ALES MRS Com munications Ltd 76 Park Rd Whitchurch, Cardiff 0222 616936 The TR-9500 brings to 70cm everything which you • FM , USB , LSB and CW . have enjoyed with the TA-9000 on the 2m band. It • Compact size 170 (6.8) x 68 12.71 x 241mm (9.61 W.SUSSEX combines the local FM contact on simplex or • 10W output on high power 1W on low power Bredhurst Electronics High St Handcross repeater with the DX facility of SSB . The TA-9500 • Two separate VFO 's with selectable tuning comes complete with up/down microphone, Haywards Heath steps of 100Hz, lkHz, 5kHz and 25kHz. W. Sussex 0444 400786 power cable and car mounting bracket. Add on the • Full band coverage 430 to 440MHz. B09 and PS 20 power supply and you have the YORKSHIRE • Six memories, the sixth having facility for a non perfect base station rig. Sit the TA 9500 alongside Leeds Amateur Radio standard repeater shift. your TA-9000 and you can both duplex on 70cm 27 Cookridge St and 2m and work through the Oscar satellites. • 1.6MH z repeater shift. Leeds LE2 3AG 0532 452657 Remember with the new generation of synthesized • Scan facilities on both memory and VFO 's.

rigs 70cm is on the move. N O W.. actua, specd.r.at.on I If • 4 ,111 0111 I it I'd l•

As the appointed distributors for Trio, we reco m mend that you purchase your Trio equip ment fro m an approved stockist (list above). Any stockist not on the list has no connection with the Trio UK sales and service organisation and cannot, despite 'F R1 0 claims to the contrary, offer any meaningful guarantee of backup service on Trio equip ment.

RA DIO CO M MUNICA TIO N June 1981 FROM THE JAPAN RADIO CO LTD

Receiving for the NRD-515 discerning few The NRD 515 is a PLL-synthesised communications receiver of the highest class featuring advanced radio technology combined with the latest digital techniques. The new NRD 515 is full of performance advantages including general coverage, all modes of operation. PLL digital VFO for digital tuning, 24-channel frequency memory (option), direct mixing, pass-band tuning, etc. JRC's 65 years of radio communications experience will give you "the world at your fingertips". The NRD 515 is but a single item from the JRC product range which extends all the way to full marine radio installations for supertankers.

NRD 515 HF RECEIVER £948.75 inc VAT

•eleeel'e» _ ti ...... r • AJ • e . . . . , E

XTLS £2.50/ CH

SR9 DAIWA SL-11600A MF-083 8-Channel 2mtr FM TUNABLE/XTAL RECEIVER 16 CHANNEL 2mtr SCANNING RECEIVER Manne Scanner -i- FM Broadcast £46.00 Inc VAT carriage £1.50 09.50 inc VAT carriage £1.50 £85.10 inc VAT carriage £1.50

R-1000 "Hear there and everywhere" The R-1000 is an amazingly easy-to-operate, • Three IF filters for optimum AM. SSB, high-performance, communications receiver, CW. 12kHz and 6kHz (adaptable to 6kHz covering 200kHz to 30MHz in 30 bands. This and 2.7kHz) for AM wide and narrow, and PLL synthesized receiver features a digital 2.7kHz filter for high-quality SSB (USB frequency display and analog dial, plus a and LSB) and CW reception. quartz digital clock and timer. • Built in 4in speaker. • Wire antenna terminals for 200kHz to R-1000 FEATURES: 2MHz and 2MHz to 30MHz. Coax terminal • Covers 200kHz to 30MHz continuously for 2MHz to 30MHz. • 30 bands, each 1MHz wide. • Five-digit frequency display R-1000 £285 inc VAT carr £4.50.

IN RESPONSE TO PUBLIC DEMAND THE ARRA NATIONAL EXHIBITION HAS MOVED TO DONINGTON PARK DONINGTON CASTLE 29130131 OCTOBER 1981 SEE YOU THERE

492 RADIO COMMUNICATION June 1981 'T RI O LOWE SRX 30D pacesetter in amateur radio a familiar name, but a whole new receiver

Trio 8400 the new way to 70cm FM mobile, a fully synthesized 430 440MHz 10 watt output, mobile transceiver with memories, 2 separate VFO's all in a truly amazing compact package. Complete with up/down frequency shift microphone and car munting bracket the TR8400 is the way to go 70cm is on the move

TR-8400 70cm FM mobile 10 I eib £279 inc VA I. Securicor carriage £4.50

A familiar name, but a whole new receiver behind it. Building on all the ex- cellent features of the SRX-30, including the drift cancelling system covering 500kHz to 30MHz; the selectable sidebands and AM; the easy to use tuning system; we now introduce the all new SRX3OD which incorporates the sug• gestions made by our customers Outstanding new features are: • Extended coverage 200kHz-30MHz • Digital readout in large green display units which give true unambiguous frequency information—even when you switch sidebands or use the clarifier. • All new frequency synthesis using Plessey SL6 1641 double balanced modulator ICs for a new high standard of performance. TR-9C00 tite exciting T R SOW 2-metre all-mode ltanscervu• • All new audio system which produces outstandingly good quality on the combining the convenience of FM With long distance sse built in speaker, and is capable of driving external hi-fi speaker units for even and cw in a eery compact, very aitordabto Package better sound Because of its compactness the TA-9000 is ideal tot mobile rnstallation, add on its fixed station accessoires and it •All new IF filters with optimum bandwidth for mode in use. Automatic becomes the obvious choice for your shack. filter selection from mode switch. There is so much that is impressive about the SRX3OD that you have to see it and handle it to really appreciate the performance. We predict that the SRX3OD will be a landmark in low cost, high perfor- mance SWL receivers. Just consider how much you should pay for a TR-9000 2 Metre Multimode receiver covering 200kHz-30MHz with accurate digital readout; high perfor- mance USB/LSB/AM with switched filters; drift cancelling frequency syn- thesis; built in mains supply and built in speaker; high quality construction £345.00 inc VAT. Carriage by Securicor £4.50 and advanced design—and so much more Then look at our price for the SRX3OD and you will be even more impressed.

£195.00 inc VAT Securicor carriage £4.50

Accessories for the short-wave listener Inc VAT Carr HF5 80-10m HF vertical. No radials required when on ground post...... 48.50 4.50 EIS Small egg insulator. Glazed ceramic 40cm long .30 .25 ER. Large egg insulator. Glazed ceramic 50cm long . .45 .36 SIL Ribbed strain insulator for dipole end or centre. 70cm long .35 .36 TR-7800 Trio's remarkable TR-7800 2-metre FM mobile transceiver provides all the features you could desire for maximum operating enjoyment Fre- MIZUHO quency selection is easier than ever, and the rig incorporates new memory development for repeater shift, priority, and scan. The TR-7800 by Trio, the KX2 Top quality 503kHz-30MHz aerial tuner. Perfect only FM mobile. match for R1000. . 29.90 1.50 AX1 Aerial switching system. Handles 6 aerials Fi 6 receivers ...... 27.03 1.00 The Ultimate 2 Metre APM1 Audio peak and notch filter. Variable bandwidth ac- Mobile FM rig tive filters . 33.00 1.00 TR-7800 SRI Mini rack for above the system 14.09 1.50 MP1 Back mount for APM1. 5.20 1 03 £268 inc VAT. Carriage by Securicor £4.50

L O W E ELE C T R O NIC S Ltd CHESTERFIELD ROAD MATLOCK DE4 51E TEL 0629 2430/2817

RADIO CO M MUNICATION June 1981 493 DAIWA Distributed in the UK by Lowe Electronics Limited.

The Daiwa infrared mike system comprising of a control box, sensor and infrared mike enables you to dispense with the hand mike and cable when operating in your car or shack. By using an infrared beam audio is transmitted from the mike to the sensor and then to the control box which activates the transmitter. To transmit. press the locking switch on the mike and talk. To receive, release the switch and your rig immediately returns to receive. When you have finished your contact return the mike to its slot in the control box and the mike nicad battery is maintained at full charge. For those of you who like fresh air and drive with all the windows open there is a matching wind shield available at an additional 75p. So there we are, the latest in technology to bring safely to your mobile operation, the Daiwa infrared mike. the DAIWA Infrared mike £45 inc VAT carr. £1.00

The new CNA1001A antenna tuner from Daiwa has already changed the whole concept of antenna tuning in the amateur radio station No longer do yOU have to fiddle with this control and that control al order to reach a match conclihon, simply push a button and lei the tuner do it tor you The CNA100IA incorporates a sensitivo reflected power detector which Monitors SWR all the time. At the fuel push of the operate button. a motor driven gearbox drives the load and match variable capacitors through their entire nos . e>

range in overlapprng small increments seeking a correct match When matching us achieved, the motor drive stops •• and that's that The CNA1001A needs only a small sniff of RF to work on (typically 5 wattsl so you needn't worry about blowing up your PA, and ri covers all the current and future amateur bands from 3-30MHz. includes switching for two antenna syslems.a 10 watt 150 watt 1 minute' dummy load and best of all includes a cross needle power and SVVR meter This section measures power from 0-200W in two ranges and reflected power from 0-40W together with the e rr unique Daiwa cross pointer SWR system All this in one compact unit requiring only 12V dc to drive the tuning Motors. tree. DAIWA CNA 1001A Automatic Antenna tuner £129.50 mià

inc VAT high power model £190 1.17C VAT

the DAIWA cross needle power meters

Until recently, the in-line measurement of RF power and SWR involved calculation or the use of two instruments. Now, DAIWA have introduced a range of power meters which provide an elegant solu- tion to the whole problem of RF measurements Utilising two toroidal current transformers to detect true forward and reflected power, and feeding the outputs to a twin movement meter with crossed pointers, it mn now possible to measure forward power I LU scale), reflected power (RH scale) and SWR twheie the pointers cross) at a single glance. The photograph shows 130W forward power, 1W reflected, and an SWR of about 2 to 1. The DAIWA CU series power meters represent the ultimate power meter for the professional and amateur alike, and are indispensable in the fully equip- ped station, Three models are currently available covering frequencies right up to 2.5GHz so there's one for you whatever your interests CN620A 1-8-150MHz up to 1kW £52.81 inc VAT CN630 140-450MHz up to 200W £71.00 inc VAT CN650 1 2-2- 5GHz up to 20W £95.00 inc VAT

The Daiwa range of rotators ara probably the best amateur rotators available The quality of construction is up to the high standaids we have come to expect from Daiwa and the rotator system is of a completely new design which eliminates "out of sync- operation and for the first time gives a true 360 indication on a circular scale based on a great elide map centred on the UK. Both the DR7500 and DR7600 can be supplied with either of the controllers available, and both upper and lower mast clamps allowing mounting inside a standard tower or an the top of a pole The D87500 will handle beams up to and including 3-element tribandes. whilst the DR7603 will handle up to and including a 2-element 40 metre beam Each rotary system is supplied complete with 10t8I01 unit, control unit, and upper and lower mast clamps rho rotators can be ordered as either -II" or -X- versions The "R" suffix denotes the contrulter with the back lit scale and control by switches marked "left - and -right" to drive the rotator round The controller pointer then smoothly indicates the direction n wheh the rotator is pointing However, as an alternative, the "X" suffix unit is of the preset type where the controller pointer is turned by the operator to the beam heading required The rotator then turns to this heading and stops Correct operation of the rotator is indicated by a discreet flashing tight on the control unit With this type of control unit. you can go into the shack, set the rotator turning to the direction you need and then do someihrng else whilst the rotator comes round Either control una can be specified with ether of the hvo rotators, e DR75COR is the smaller rotator wath the round control whilst DR 7500X us the same rotator, but with the preset control unit. the DAIWA rotator systems DR7500X £98 inc VAT DR7600X £135 inc VAT DR750OR £108 inc VAT DR760OR £144.90 inc VAT L O W E EL E C T R O NIC S Ltd CHESTERFIELD ROAD MATLOCK DE4 51E TEL 0629 2430/2817

494 RADIO COM MUNICATION June 1981 THE SHIMIZU SS105S 80-10 metres ssb/cw transceiver

...... This super new transceiver covers 80-10 metres, gives 10W out and is smaller than 411. anything else we have seen so far Ideal for transverter driving, the SS1055 has FM transmit and receive options as well as excellent performance on SSB/C W for l'IF band use. The SS105S is supplied in semi kit form so as to keep down the price, but all ifie and mixer boards are ready built and aligned so no test equipment is required All the cabinet work has been carried out so all you have to do is assemble the IF strip, xtal oscillator, and lit them to the completed chassis Great idea and it brings back the flavour of home brew with the added advantage that the rig will work when you've finished it. For more info, lust ask us or come along and see it It's a great little rig NETT inc VAT CARR

SS015S 80 lOrn solid state SS8 JCW/FM transceiver Sena ka form 2256 7500 258, 7165 4 50 SE-N8 Noise blanker kit SE-PriAta RX FM discriminator kit 1500 17 25 1 00 SE•FMix TX FM generator kir 11 00 12.65 t SE-MK RX marker kit 960 11 04 50 05 CWF 500 CW Mel 19 50 22.43 50 Optional band crystals 3 00 3 45 25

AR 22 2 metre FM pocket synthesized, 141-149MHz receiver.

AR 2 40 A 2 metre hand held synthesized 144-146 a- watt transceiver

AR22 £83 inc VAT. AR240A £158 1.17C VAT. Carriage £1.50. Also available is a marine version of the AR22 the AR22M, 156-162MHz £89. SX 200 SCANNING MONITOR The SX 200 scanning monitor receiver will enable you to en- toy a new dimension of scanning ease, convenience and ef- ficiency Many thousands of frequencies at your fingertips These frequencies can be easily selected by keyboard opera- on, and can be monitored, searched. scanned anti inemonsed at will, without the need to purchase expensive crystals An additional feature is the accurate digital clock which assists accurate log keeping The receiver covers amateur VHF and UHF Irequencies, both repeater and simplex contacts between amateurs can be monitored Also available are aircraft and marine Ire quencres but please note, a licence may be required to legal ly listen to certain frequencies within the performance range of the SX 200 in some countries So there we are. the SX-203. a precision instrument designed by J I L to give not only ease and efficiency in use but hours of enioyment ether at home or in your car SX 200 £237 inc VAT carr £4.50

FREQUENCY COUNTER Model HFC 55 The HFC55 is a sensibly priced, easy to use d (;tai Irequency meter covering 10kHz-55MHz in a singlei range. The bright 5 digit display gives a direct reading of frequency when the built in telescopic aerial is placed near a source of RF The HFC operates fr ern internal dry batteries and is housed in a strong metal case to withstand regular and continuous use HFC 55 Frequency Counter £36.50 inc. VAT. Carriage £1.50 POWER SUPPLY UNITS the PP1305 4 amp 13.8 volts d.c. £18.40 inc. VAT the PP137 7 amp 13.8 volts d. c. £32.00 inc. VAT. the PP1310 10 amp 13.8 volts d. c. £49.50 inc. VAT.

Carriage £2 NOIE THE PRICES WITHIN OUR AOVERTISEMEN I All! ¡ L i A Zi U F Il-4 E a H A l-' HIL l;

HEAD OFFICE AND SERVICE CENTRE LOWE ELECTRONICS LTD, CHESTERFIELD ROAD. MATLOCK. DERBYS. TEL. 0629 2817 or 2430. TELEX 377482 OPEN TUES FRIDAY 9 5.30. SAT 9 5 CLOSED FOR LUNCH 12.30 TO 1.30 For personal attention on the South Coast contact John, G3JYG, 16 Harvard Road, Ringmer, Lewes, Sussex Ringmer 812071. For equally helpful attention in Scotland contact Sim, GM3SAN, 19 Ellismuir Road, Baillieston, Nr. Glasgow. 041-771 0364. SEND 48p IN STAMPS FOR COMPLETE CATALOGUE AND ANTENNA BOOK. PLEASE SPECIFY ANY PARTICULAR INTEREST AND WE WILL SEND FULL INFORMATION

RADIO COMMUNICATION June 1981 495 «. Thanet Electronics for CI) IC OM the amateur's professional friends * Buy direct from us and get two years warranty on all equipment *

It's not the size that counts it's the Quality

IC-2E Handy Talky £159 INCL. CHECK THE FEATURES I-5kHz SWITCH - adds 5kHz to the FULLY SYNTHESIZED - covering indicated frequency. 144-145.995 in 400 5kF17 steps. DUPLEX SIMPLEX SWITCH - gives POWER OUTPUT - 1.5W with the simples or plus 600kHz or minus 600 9V rechargeable battery pack as supplied kHz Transmit. - but lower or higher output available HI-LO W SWITCH - reduces power Out. with the optional 6V or 12V packs. put from 1.5W to 150m W reducing EINC ANTENN A OUTPUT SOCKET - battery drain. 50 ohms for connecting to another EXTERNAL MICROPHONE JACK - antenna or use the Rubber Duck supplied. If you do not wish to use the built-in electret condenser mic an optional SEND/BATTERY INDICATOR - Lights microphone/speaker with PTT control during transmit, but when battery power can be used. Useful for pocket operation. falls below 6V it doesn't light indicating EXTERNAL SPEAKER JACK - far the need for a recharge. speaker or earphone. FREQUENCY SELECTION - by This little beauty is supplied ready to go thumbwheel switches, indicating the complete with nicad battery pack, frequency. charger, rubber duck.

Enjoy VHF mobile The Latest at it's best-IC-260E 2M Multimode The IC-260E offers such extras as full frequency read out, upper and lower sideband, and scanning as well as Base Station FM and CVV. Thus, it makes an ideal base station, when Facilities include: FM,USB,LSB and CVV. used with a DC power supply, as well as a mobile. Now Built in scanner and memories. Bright supplied with up-down scanning mic. green digital readout.

£339 INCL. only £479..,. IC 251E

On these, and all our other products: • Free delivery for all transceivers, using registered first class post • H.P. and Part Exchange welcome. All prices including VA T. SEND FOR TECHNICAL DETAILS Also available from our shop in Herne Bay are: • ANTENNA SPECIALISTS

a` MICRO WAVE MODULES e J-BEAM WESTERN YAESU MUSEN RSGB PUBLICATIONS G-WHIP BEARCAT VIDEO GENIE COMPUTERS IMPORTANT We would like you to phone, or write to us so that we can give you as much detailed information as possible on any particular product. Use our 24 hour ansafone when calls are cheap.

143 RECULVER RD., BELTINGE, Ce HERNE BAY, KENT. =Elcm, irhanet for ICO M Tel: 02273/63859

496 RADIO COMMUNICATION June 1981 A Great Little Baby The Portable Pair Covering all bands from 80m - 10m including the new ones ' 13 8V DC operation 100 watts RF output 140W IC-202S £169inc on AM) • TWIN VFO with in band duplex available ' IC-730 The IC-202S os a very well designed 2m Modes USB. LSB. CW and AM.• SSB portable. II offers: 3W pep output on Digital readout with 3 tuning speeds down to 10HZ USB. LSB and CW ' Large Battery capacity steps.' (HP11 type) or Nicads if you wish ' A Noise blanker. • Switchable preamp' special VXO circuit to provide smooth tuning RIT IF Shift' Dial lock and of course the usual SUPERB and crystal stability needed for 558 ICOM quality and performance ' £549 Operation on 2m Each of the four 200k Hz band positions allows operation anywhere in

Supplies will be slow at first so II you are interested, call 2m (Supplied with 144-144 2 and 144 2- us and gel your name on the list for further details. inc 144.4). ' Top of the band Oscar xtats available for "cross-pond working" • It has a DC socket and S0239 sockets for mobile or base station working, barefoot or as a prime mover. • Mobile mounting brackets. Nicad = ME , packs, chargers, cases all available options. MI. You must agree, a very versatile well proved rig The 70cm twin of the 202S having very Mir in MI f similar features, covering the frequency range of 432-435.2 MHz. Their versatility is well worth an enquiry.

Some features. All over the World • 9 Bands Top Ten including new ones! • General Coverage Receiver - 100KHz to 30MHz. • Tuning down to 10Hz steps - YES! 10Hz - yet they haven't been able stable as a rock l * Built-in Speech Compressor which really gels excellent reports. to get enough! . The famous ICOM Band Pass Tuning. • Memory - it even does all the band changing for (But things are getting better) you • Self cancelling RIT. • 3 rates of Tuning. . Two Independent VFOs (in band duplex possible). • 100 W Output. • Modes AM.SSB.C W and RTTY. A lot in a small packet for £795 inc. VAT (13.6V operation - matching mains PSU £100) • Solid State 500W linear available shortly IC-720A

ICO M's new 9-band HF Transceiver - the IC-720A beats the tot £795 incl IC-255E Now , An experts eV/ FRO °V EDrildi j mobile choice T.END 1

25 Warts - 5 Memories - Scanning - 600kHz AND User Selectable Repeater Shift - Full Coverage in 5kHz or 25kHz Steps. Crystal controlled Tone Burst Alternative program mable shill Full band coverage - extendable to 148MHz it required • Reverse Repeater tactlities Four digit LED display • RIT 1 3kHz tor those oil channel stations) 25 Watts output or 11N low power • Scan control from the micrOPhone (optional mic available' A superb receiver using grounded gate F ET front end • Good loud audio Scanning over a user Program mable range • Optically coupled tuning between control knob and CPU Memory scan • Multrway 24 pin socket on back for iouchpacl. computer or external control Stop on empty or busy channels Rugged modular RA (Guaranteed ot course I Tuning in 25kHz or SkHz steps Mobile mount which can be padlocked 5 Memories - retained while the power is connected to the rig • Up.down scanning microphone available Bullt•in 600k Hz Repeater Shill CAN YOU RESIST SUCH A TEMPTATION

TELEX: 965179 Thanet for ICO M =Ulm

RADIO COM MUNICATION June 1981 497 Tono Theta 7000E IC-451 UHF Base Station A great computer ICOM are proud to announce the introduction of the 70cm version of their famous 2m base station — the IC-251. Of course, it is engineered to the usual high on offer from Thanet ICOM standards and includes such features as:- * 3 memory channels TM. new TU(TA 7000E meant that me., Ant.... 2 DAR. 32.10 • 15 Itne NMI Kremn In. R• e Automatic repeater shift on switch-on tan en., In, ...al dtsplay nt CW $115V and Tx.1 teguned • Autornattc ttenvntrtecet. ASCII A Rath tranymt and cecene model And teolCh • Ann node tutu. • pelt, / haIled up connect the t ONO to any TV wIne. the On,osOfe I Cnannellol etch.; ' Send lunCIAn * Additional selectable shift for European DX ter en 'mat o. to • pade Punt.' Ito., the ostalld • Bulle entemocy 53 ettalacter type attead.•un 11.11 ‘011 ••led Ottne ula yen» , CW speed n recetytn4 nut ItoncImn • Sunultanernta +net% Ill the menu,. y * Selectable channel steps for FM (supplied with 't• MM .,' be ettne. «Refloat rec. ..l cynt 53 chat at I. type an nOm teCoNted cooed*, COooKllOo lo the LE lime leedl cancel tun. .., • Co.... cnnt•ut 25KHz — others are diode programmable) nanacetret It 0,41 the •ey. Phone and n1d Mckett luncteon • Wont mide ope•atton • Automat. C71 ,11-F 177. GO nt HO Ova pet Any' Ecnn tuner.. * Full power control on SSBÍCW/FM Some of he Ouniandene Features COMMUNICATIONS COMPUTER I HE TA 0 70011E * Superb receiver performance using MOSFETS UHF and Comoottle %hen Output • Pt.,. • Weld Wmp mount, function • t /antm .tecetre alterlace • W.> tinge ot namenttttne ano leCeovAp tn ASCII mode col nit ," • Cw * Multipurpose scanning weeds - 10CW weed; • 8011V • tp lum von • Math and tweak. Ispace and meal? demodulate,l Ion he swa m/ranee lot I 70. 475 system • Mona,. coca. S Cte macttce lunconn • * Covers 430-440 MHz and 820 tit Mal • Ccyltal controlled en.autaup • Vat tab?, CW *05014 • Cross pattem theca mg In. ASEK ot to tone • Conyentent ASCII Output term ., • Lod compute , output most. . * Xtal controlled Toneburst tt eat attended... • Lamle Catmetly dttotae men. , • Teat message tunctton IRy and (1131. e Cool running power supply to , 0, ol Reiman., It! und £579 inc. V.A:T.

The famous IC240 has finally been replaced. Many thousands are in use and its popularity was due in part to simplicity of operation. sensitivity and superb audio on TX 'NEW' IC 24G and AX. The new IC24G has these and other features:- Full 80 channels selected by easy-to-operate press button thumbwheel switches. Readout is by channel numbers. le: S21-521. S16=516 and for the lower part of the band 144.5 =420 This readout can be clearly seen in the brightest of sunlight. Duplex and reverse duplex is provided along with a crystal controlled tone call. Hi-10w and lo-1w RF output is available, along with a 12'r2KHZ upshift, should the new channel spacing be necessary. The old IC240 proved to be the most reliable rig we have ever sold — the IC24G. because it is so similar, looks like following the same pattern. Remember, for mobile use a rig MUST be easy to operate to be safe. SEND FOR TECHNICAL DETAILS

£ 1 6 9 INCL

AGENTS (PHONE FIRST — All evenings and weekends only) Scotland Jack GM8GEC 1031-665-24201 Midlands Tony G8AVH 1021-329 23051 Wales Tony GW3FKO 10874 27721 North West Gordon G3LEO Knotsford (0565) 4040

498 RADIO COMMUNICATION June 1981 WELZ SVVR/PO WER METER £29.95 inc VAT WATERS i& 400W 5-BAND ATU £49.95 inc VAT Here's a couple of new units from Welz that are of particular interest to HF operators with solid state STANTON transceivers. The units are available either separately or can be linked together to form a single unit. The AC35M comprises a 5-band ATU ELECTRONICS with a power capability of 400W pep and will match your transceiver 18120 MAIN ROAD, HOCKLEY, ESSEX. Tel: (0702) 206835 to coax feeder. The matching SP. 15M is a combined SWR meter and power meter covering 1 -8 to 150MHz. Three switched power leads are available, 2.5, 20 and 200W. FM MOBILE TRANSCEIVER! M700EX 2m FM 25 WATTS t IJ i £199 inc VAT The Multi 700EX now a firm favourite with amateurs throughout the world —it embodies all the essential features of a completely self contained FM station. Its punchy 25 watt signal beats all the old 10 watt transceivers hands down. The large digital display gives clear and precise frequency readout, controlled by a "click stop" frequency selector knob that provides steps of 25kHz with an additional 12+kHz selector. Priority scanning provides for the scanning of preprogrammed channels plus the main dial channel. Repeater operation is taken care of by means of a 600kHz down shift selector and automatic tone-burst switch. For listening on the input frequency of the repeater, instant reverse repeater operation is available at the SEND FOR FULL COLOUR BROCHURE touch of a button. Local contacts are taken care of by a continuously variable power control that enables power to be reduced right down to 1 watt.

3-5VSWR:PO 150MHz WER (11.95 FIELD 'nu STRENGTHVAT • 65p p&pMETER TELLS THE GLOBAL TV FILTER TRUTH HP4A e £5.95 "WEL2' We are pleased to announce the m ar introduction of the new MODELS SP200 1-8 160MHz 20W 200W I kW E49.96 GLOBAL HP4A TV filter. Even more effective than earlier S P300 1.8 500MHz 20W 200W lkW E69.951n.c.1 SP400 130 5130MHz 5W 20W 150W £4.9,951n.c.) models, its double action filters There really is no excuse for not owning one of these both inner and outer coax con• Welt VSWR/POVVER meters are high quality in- little units. Its a combined SWR meter, power meter ductors. Ideal for both VHF and struments approaching laboratory accuracy. They are and field strength meter covering HF and VHF bands HF operators, it is now so effec- capable of providing extremely accurate 3 IsomHz. It tells you all you need to know about tive it should solve most cases of measurements of both power and voltage standing your aerial system either mobile or fixed and gives an interference caused by RF down wave ratio. Features include high sensitivity 12.5 W indication of power output and field strength Each the TV aerial lead. Keep one full scale 1-8 500MHz). Er completely flat response. any is fully guaranteed for 12 months handy ,

e THE 'LONG JOHN' STILL THE MOST SENSITIVE MONITOR ON í í WELZ DU M MY LOAD SUPER GAIN 50 OH MS 50 WATTS THE MARKET TM56B inc VAT VERTICAL DC 450MHz 1 £19.96 e> E7.95 A highly compact vertical aerial that will more than double your effective radiated power. Only 4h tall yet really outclassing Here's a new item that is manufactured by WELZ and all its similar sized competitors. Con- ,s a true laboratory type piece of equipment at a price struction features high quality plated you can afford. This 50ohm dummy load will handle Two models are available, one for ho marine ban,. aluminium and stainless steel fittings. The powers of up 10 50 watts and is fitted with PL259 and one for the amateur band. Each model corne, base matching section is fully protected plug. Not to be compared with some inferior units fitted with 10 popular channels with a total capability against the weather and the $0239 about, this model is rated at up to 450mHz with a of 16 channels of which four can be continually scan socket is fully shrouded. The aerial comes VSWR of 1:1 and is offered at this price because of a mid. The TM56B can be operated from an externiii complete with mast mounting clamps. special bulk purchase. 12V DC source or from its own internal 240V AC sun The "Long John" really packs a knock ply. The loudspeaker is built into the base 01 this most ',sp out punch. sensitive monitor. %. I

2m FM 25 Watts AZDEN PCS 3000 £219 inc VAT Here's a really super action packed FM mobile transceiver. Particularly ideal for the operator with very little room to accommodate the standard size of transceiver. The detachable head unit may be mounted remote from the main transceiver (optional cable kit necessary) so it can be tucked away in the smallest of spaces. Apart from this novel practical feature, there is a host of technical features. A microcomputer control panel takes care of frequency control, 8 memories, band and segment scanning, all selected by touchpad controls with back illumination. Full coverage of 144 to 146MHz is available on 25kHz or 14kHz steps, a bar LED signal and RF meter gives positive readout as does the large LED frequency display. Other features include high,- low power switching, repeater shift, tone burst, tone entry indicator, ni-cad memory back-up and much more. Why not send today for the lull colour brochure?

SEE ORDER FOR M ON PAGE 501

RADIO COMMUNICATION June 1981 499 DELIVERY BY SECU RIC OR J Order by post or telephone with confidence - YOtill receive your order in 72 hours by FAST AND FRIENDLY Securicor or post (aerials excepted). M AIL O R D E R - Any where in U K H E A V Y P A R C EL S - Sec uricor O T H E R P A R C EL S - Parcel Post or British Rail Such nice people' All goods sent are covered free by our own insurance _e-d-•‘›

WATERS Et All prices Carriage charge include VAT PRICE LIST-JUNE 1981 in brackets STANTON

TRIO FT707S 160- 10m 8 band transceiver 454.001n.c.1 MAID600P 600MHz prescaler 23.00 ) .65) TS830S 160-10m transceiver 9 bands £639.52 15.00) FT707 160-10rn 8 band transceiver 529.00 Inc.) MMDP1 Frequency counter probe 11.501 .65) VF0230 Digital VFO with memories 194.45 16.00) FP707 230v AC to 12v DC for F1707 109.2512.931 MMA211 tOm preamplifier 14.95 1 .651 AT M All-band ATU power meter 106.72 12.251 FC707 160 10m atu 80.50 11.501 MMA144V 2m RF switched preamp 34.90 I .65) SP230 External speaker unit 33.14 11.50) FV707DM External digital vfo for FI707 188.30 in.c.1 MMA1296 23cm preamplifier 29.90 I .65) DS2 Optional dc pack for TSEGOS 39.90 11.501 MR7 Metal rack for FT707 14.95 (1.501 MMF144 2m filter 9.90 I .65) DFC230 Dig fequency remote controller 163.13 11.50) MM82 Mobile mounting bracket F1707 18.00 11.50) MMF432 70cm filter 9.90 1 .661 YK88C 500Hz CW filter 28.7511.001 FRE1707 21.95 (1.001 MMV1296 70cm-23cm varactor tripler 34.50 1 .651 YK88CN 270Hz CW filter 28.75(1.00) FL21002 160- lOrn 1200watt linear 9 band 385.00 (n.c.) MMS384 384MHz frequency source V.60 I .65) TS530SE 160- 10m trans 200w pep digital 506.0014.501 FT225RD with digital readout 5135.01:01n.c.) MMR15/10 15db attenuator. BNC terms 9.90 I .651 065 Digital readout 103.60 11.501 TH55 Bohm headphones 9.96 11.25) JAYBEAM ANTENNAS SP520 Speaker 17.25 11.501 FF501 Low pass filter 19.96 1 .75) 183 HF 3 element Tribander Beam 167.93 14.501 VF0520S External VFO 98.90 14.501 OTR24D 24 hour quartz clock 25.7011.50/ VR3 HF Vertical Triband 42.50 13.001 YG3395C CW filter 8 pole 37.95 I .501 FP12 230v AC 12 amp DC p/supply 78.20 12.501 4 metre Antennas DK520 DOS to older TS520 10.351 .75) FP4 230v AC 4 amp DC p/supply 41.4012.501 4Y/4M 4 element yagi 20.7013.001 SM220 Station monitor scope 197.8014.501 FSP1 9.6011.00) PMH2/4M 2 way phasing harness 12.20 (1.031 BSS Pan display 158.20/100/030 48.301 .501 FRG7 • 5-33MHz communications Re 189.00 Inc.) 2 metre Antenne. 1355 As above for 1S520 48.30 I .501 8HRG7 Battery holder for FRG7 5.00 11.031 DCI iWB Wide band discone 1103 470MHzl 41.40 (2.50) R820 Amateur band receiver M0.00 14.501 TC500J Frequency counter 189.75 In.c.) LR1/2M Omnidirectional vertical 24.15 12.501 YG455C 500Hz CW filter 58.66 1 .501 YCSOOS Frequency counter 270.25 In. c C5/2M 5dB glass fibre colinear 44.30 (3.50) YG455CN 250Hz CW filter m oot .50) TC500E Frequency counter 345.00 Inc.) 5Y/2M 5 element yagi 11.25 12.001 YG8f3A 6kHz AM filter 34.60 1 .501 FRG7700 1981 version of FFIG7000 309.00 Inc.) 8Y/2M B element yagi 14.60 (2.50) TSIBOS 160-10m S/State transceiver 179.65 14.50) FRG7700 MEM As above with freq mem 390.00 Inc.) 10Y/211/1 10 element 'long yogi' 31.00 (3.50) VF0180 External VFO 96.6011.501 M O M 144 146MHz synthesised h/h 199.00 lase.) 013M10/2M 10 element Parabeam 36.80 (3.50) SP180 External speaker unit 36.13011.501 Ni-cad 230v AC charger 18.98 11.50) PE1M14/2M 14 element Parabeam 44.85 (4.50) AT180 Matching 200W antenna tuner 96.46 14.50) NC2 Ni-cad 230v AC fast charger 39.68 11.50) 5XY/2M Crossed 5 element yaw 22.76 (3.03) YK83C 500Hz CW filter 22.7s .501 NC9 Ni-cad 230v AC charger 7.48 1 .75/ 8XY/2M Crossed 8 element yagi 29.40 (3.53) YK88S Second SSB filter option 28.461 .50) U PS Spare ni-cad battery pack 16.68 1 .75) 10XY/2110 Crossed 10 element yagi 37.70 (4.00) P530 AC power supply for Ts180s 85.10 14.50/ FLC2 Heavy duty case 20.70 ( .751 X6I2M/X12/70cm Dual band crossed yaw 38.50 (4.501 TSI30S 8 bend 2013W pep 491.05 (4.501 PA2 12v PSU 16.69 11.001 PMH/2C 2 way phasing harness 7.50 .751 TS130V 8 band 201N pep 404.34 14.501 F8A1 Ni-cad pack charging adaptor 2.59 .35) 0412M 4 element quad yagi 23.70 12.501 DFC230 Dig frequency remote controller 163.13 11.50) F1225R 144-146MHz Base station 620.00 In.c. I 0612M 6 element quad yagi 31.40 (4.50) TS120S 80- 10m 200W pep mobile trans 3E9.0014.501 FT225RD 144-146MHz with digital readout 585.00 Inc.) 05/2M Double 5 slot-fed yagi 20.16 (2.53) TS120V 80-10m 20W pep mobile trans 347.3014.501 MEMT225 Memory option module 92.00 (n.c.) D8/2M Double 8 slot-fed yagi 27.16 (4.03) 71120 200W pep linear for TS120V 128.8014.501 0151225 Digital readout for FT225R 57.50 (1.001 SVMK/21/1 Kit for vertical polarisation 7.25 (1.501 M8100 Mobile mount for TS120/130 17.25 11.001 FT48OR 2 metre 10W FM transceiver 369.00 Inc.) UGE1V2M ground plane 10.15 (1.501 YK88C 500Hz CW filter 28.751 .501 F172OR 2m/4m/70cm control head 120.00 Inc.) H0/2M Mobile 'halo' head only 4.60 (1.50) YK8BS 2nd SSS filter option 28.451.50) sn Switching box 56.00 Inc.) HM/2M Mobile 'halo' with 24 - mast 5.40 11.75) VF0120 External VFO 89.7014.501 E725 2m of connecting cable 23.00 11.001 PMH2/2M 2 way phasing harness 9.90 WOW SP120 Base station external speaker 25.313 11.251 6721 4m of connecting cable za.00 11.00) PMH4/2M 4 way phasing harness 23.00 (1.75) SP40 New mobile speaker unit 26.8911.501 720RV IOVV 2m module 133.00 In.c.) 70cm Antennas AT130 100VV antenna tuner 72.69 (1.501 720RVH 25W 2m module 143.00 Inc.) C8/70cm &18 glass fibre colinear 50.00 (3.50) PS20 AC power supply 15120/130V 44.B5 14.501 720RU lOW 70cm ;nodule 156.00 Inc.) D8/70cm Double 8 slot-fed yagi 20.70 12.501 PS30 AC power supply TS120/ 1305 M.1014.501 MMB3 Mobile mounting bracket 5.00 0.501 PBM18/70cm 18 element Parabeam 25.30 12.501 MAS 5 band mobile aerial system 74.7514.50) NEW FT290 2m FM/SSS/CW portable 299.00 1n.c.1 MEIM48/70cm 48 element Mulribeam 28.75 13.001 TL922 160-10 metre 2KW linear 596.7014.501 Available end of May approx. M8M88/70cm 88 element Multibeam 39.30 14.50/ MC50 dual i-npedark.e desk microphone 24.1511.501 13XY/70cm Crossed 8 element yagi 34.15 13.50/ MC35S Fist microphone 50K impedance 13.6011.001 12XY/70cm Crossed 12 element yagi 42.32 (4.50) MC305 Fist microphone 503ohm imp. 13.60 11.001 FDK VHF/UHF EQUIPMENT PMH2/70cm 2 way phasing harness 8.50 11.130) LF30A HF lowness filter. IkW 18.4011.001 M700EX 2m FM 25 watt trcvr. I2v DC 199.00 Inc.) PMH4/70cm 4 way phasing harness 18.00 0.501 M750E 2m F61/10W grew 12v DC 299.00 In.c.) RD300 IkW oil filled dummy load 48.3011.501 23cm Antennas 189.05 TS770E 2m/70cm all mode transceiver 730.25 14.501 Expander 70cm transverter 015/1296 Double 15 slot-led yagi 34.133 (1.50) 69.0012.501 SP70 External speaker unit 18.4011.001 PS750 230v A.C. power supply PMH2/23cm 2 way phasing harness 25.40 (1.001 Palm II 2m FM 6 channel portable 89.00 in.c..1 TR9000 2m synthesised mullimode 345.00(4.50) Matching Transformer Palm IV 70cm FM 6 channel portable 149.00 Inc.) TR9503 70cm all mode t.b.a. M175/50 Impedance transformer 75/5031 3.60 ) .50) 181 1750Hz tone burst 10.00 Inc.) 809 Base plinth for TR9030 32.20 14.931 Chimney Lashing Kit TR7930 2m FM synthesised mobile 288.0014.931 Multi 3CO3 2m FM/10 wart base station 399.00 Inc.) TM5613 2m FM monitor 230v/12v DC DL Double lashing chimney im 8.25123301 TR2300 2M FM synthesised portable 168.7514.501 89.90 In.c.1 11.00 1 .501 Wall Brackets Vf32300 IOW amplifier for TR2300 49.46 11.50) FDM4OSP Speaker/mic for Palmsizer CC2 Leather case for Palm 11.'1V W6 e wall bracket CI 3 masts) 2.86 (1.03) MB2 Mobile mount TR23C0/VB2300 17.2511.001 5.75 1 .50) 4.601 .50) W21 zr wall stand-off bracket 10.36 (3.00) RA1 Rubber flexible antenna 6.901 .50) BC2 233v AC battery charger SC2 leather case for Palmsizer 9.75 1 .50) W24H0 24' wall stand-off bracket, 14.70 (4.50) PS1230 AC power unit and charger 29.5011.50) Masts (Aluminium' TR2400 2m FM synthesised handheld 198.9614.501 882 "AA" sire external battery case 5.00 1 .50) $12 Ni-cad battery pack 12.00 1 .50) SPM 16' v 1" Portable Mast 15.1613.001 S11 Base stand and quick charger 43.7011.501 PME 4' extension for double arrays 2.50(2.00) BC5 12V quick charger 17.2511.501 Xusks for Palm II and Palm IV 3.001 .15) Xtaks for TM568 2.50 .15) A4 4' e 13- straight 3.01:1 (1.50) SC3 Soft carrying case. 11.50 1 .50) A5 x 1' straight 2.30 (1.53) LH1 Hard leather holster 18.50 1 .501 A9 e a 1r straight 6.150 (2.50) PB24 Spare battery packicharger lead 14.2611.501 MICRO WAVE MODULES A10 10' x 2" straight 12.55 1240) 99.00 1.75) TR3200 70cm FM portable transceiver 164.4514.501 MMT28/144 lOrn linear transverter Al2 17 xr straight 14.95 12.501 PL1 Spare power.' charge lead 1.301 .151 99.00 1.75) MMT144/28 2m linear transverter A14 14 x7 straight 17.40 13.001 R1003 Gen. Coverage Receiver MMT432/28-S 70cm linear transverter 149.00 1.75) 226.2014.50) Accessories 184.00 1.751 YAESU MMT432/144-R 70cm linear transvener CPI Cross-over plate 2' x 2' 3.36 0.90) 529.00 In c.1 MMT70/28 4m linear transverter 115.00 1.75) FT1012 160-10m 9 band transceiver FM JBL59/ 15 IF jointing sleeve for 2" masts 6.60 (1.50) 115.00 1.751 FTIOIZD as above but with digital FM 599.00 Inc.) MMT70/144 4m linear transverter JBL29 u/v clamp II" boom to 7 mast 1.60 ( .75) 184.03 2.251 r 0161012 Digital kit 88.25 In.c.) MMT1296/144 23cm linear transverter JBL30 u/v clamp r boom to r-7 mast 1.60 ( .75) MML144/25 2m 25W linear amplifier 59.00 1.75) 11CT101Z 12v DC adaptor 34.6011.001 JB1.53 12/ii clamp 1" boom to 1--r mast 1.461 .75) 77.00 1.75) FV1012 Remote VFO for FT101Z/ZD 121.00 In.c.) MML144/40 2m 40W linear amplifier JBL58 Guy wire clamp: non-rotating 1.50 .75) 142.60 2.75) FT107M 160- 10m band transceiver 690.00 In.c.1 MML144/103 2m 100W linear amplifier JBL63 u/v clamp 1' 11" boom to MML144/100P 2m 100W linear amplifier 142.60 2.75) FV107 Remote VFO for FT107 etoo Inc.) r -2- mast 1.40 ( .75) 102.0011.50) 77.00 1.75) FC107 160-1 0m atu, aerial switch, p / meter MML432/20 70cm 20W linear amplifier .18L64 Die-cast clamp r boors tor mast 1.20 .75) 119.00 2.7$1 FP107E 23> AC power supply for FT107 108.95 12.501 MML432/50 70cm 50W linear amplifier J8165 Die-cast clamp r boom to FP107 As above but fining internally 97.7612.501 MML432/100 70cm 1001N linear amp 229.65 2.751 1- -2" mast 1.30 .75) FTV107 Transverter nain frame 110.40 Inc.) MM21100 RTTY to TV converter 189.00 1.751 JB173 HO clamp II- boom to 27.90 .651 Lay FTV107121 Transverter main trame 207.00 In.c.) MMC28/144 10m converter 1"-r mast 2.10 (1.00) 101.20 Inc.) 27.90 .651 144V107V901 2 metre transverter MMC50/72 6m converter MOP Mast base plate for 2' mast 3.60 0.501 50V107V901 6 metre transverter 89.00 Inc.) MMC70/28 4m converter 27.90 .661 430V107V901 70cms transverter 175.95 In.c.1 MMC70/28L0 4m convener 29.90 .651 STANDARD VHF/UHF SPICI7P External speaker in cabinet 57.50 12.501 MMC144/28 2m convener 27.90 .651 C800 2 metre portable scanner receiver 79.00 In.c.) SP107 External speaker in cabinet 27.60 (2.001 MMC144/2810 2m converter 29.90 .651 C8600 2 metre FM mobile transceiver 251.00 In.c.) CIMSTIO7 12 channel memory 88.'15 In.c.) MMC432/28-S 70cm converter 34.90 .651 C711(111 70cm FM mobile transceiver zrt.00 (n.c.) CW CVV filter for FT107 23.001 .931 MMC432/ 144-S 70cm converter 34.90 .651 & WHIP MOBILE ANTENNA RANGE AM AM filter for FT107 23.001 .501 MMC435/51 70cm ATV converter 34.90 55) Tribander Helical for 10/15/20 metres 24.75(2.00) YNt34 50Cohm desk mic FT707/FT107 18.80 11.501 MMC435/600 70cm ATV convener 27.90 .651 LF4Orn Coil for above 6.551 .501 YM35 533otrn upidwn inc FT70//107 12.651 .751 MMC12913/28 23cm convener. 10m output 32.20 .65) LF80m Coil for above 5.551 .50) YM36 503ohm noise cancelling F1707/107 11.901 .751 MMK12:36/144 23cm converter, 2m output 59.80 1.751 LF160m Coil for above 6.651 .50) YM37 503ofirn manual mic F1707/107 8.151 .751 MMD050/ 500 500MHz digital freq meter 69.00 .65) LP telescopic resonator whip 3.351 .751

500 RADIO COMMUNICATION June 1981 AMATEUR RADIO CENTRE OF THE SOUTH- well worth a visit FIVE MILES FRO M SOUTHEND-ON-SEA- WHY NOT BRING THE FAMILY?

Base mount single hole fixing i 3m cable 4.501 .50) 70cm Auto switching pre-amplifier 24.731 35 3-30MHz Broad band dipole 29.0011.001 40.0011.001 AERIAL ROTATORS (complete with control 'boxes) 2m preamplifier 14.96( 35 Mosley ROS all-band dipole CDE AR40 15 core cable) ss.to 1 _50) 70cm preamplifier 17.731 .35 AIR BAND PORTABLE MONITORS Channelmaster 9502 13 coral 42.0012.001 2-40MHz pre-amplifier auto switching 18.661 .35 Is» also VHF/UHF Monitors) Sky King SU200013 core/ 36.00(2.00) 2-40MHz pre-amplifier 11.731 .35 PA3 miniature 2m pre-amplifier 8.001 .35 SHARP FX213 tuneable receiver 13.601 .751 Sky King SU4000 (6 core) 75.00(2.501 INGERSOLL MW/FM/Airband monitor 12,961 .751 KR 40ORC 15 core) complote 099.0012.03) PA70 miniature 70cm pre-amplifier 10.001 .35 47.1511.50 R517 Tuneable+ 3 Xtal controlled chan's 49.50( .75) CDE alignment bearing 7.7511.00) Z Match Aerial tun unit 1-8-30MHz 500W Channelmaster alignment 11.7541.00) EZITUNE Aerial tuning aid 30.481 .75 MISC STATION ITEMS IAMBIC Key« 34.501 .75 HF ANTENNAS (various manufacturers) SEIF 13.8V 4 amp AC power supply 12.9612.00 28.0012.00 Mini-Products HO-1 20/15/10m 2 el 96.5012.50) 2 METRE PORTABLES PS125 6 amp AC power supply 29.0011.00 Mini-Products C4 20/15/10m vert dipole 48.5012.00) SB2M 2m SSB portable 94.00(n.c. EK121 Katsumi Electronic Keyer AR245 2m FM synthesized handheld. 5W 178.00(1.50 EKM12 Matching side tone monitor 10.9611.00 Mosley TD3JR 20/15/10m wire dipole 34.5011.50) CW2A general purpose morse oscillator 8.Z1 .65 Mosley "Mini-Beam" 20/15/10m 2 el. EOM 99.0012.00) AR245 carrying case 4.101 .50 10.1501 .75 Mosley "Mini-Beam" 20/15/10m 2 at. ?kW 129.0012.00) AR245 optional helical 4.10( .50 Telegraph ON key Imanuall YW3 Twin SWR/Pwt/ Field strength meter 11.961 .50 Mosley TA32 20/15/10m 2 el. 89.7012.00) AR245 12V DC car adaptor/cherwr 4.10( .60 MF210 Self powered 2M FM monitor 12.961 .50 Mosley TA33 20/15110m 3 element 133.4012.50) VHF/UHF MONITORS FX1 d/I station w/meter 700kHz -250MHz 28.0011.00 Mosley Mustang 20115/1 0m 3 element 2kW ise.iso.o3i TM568 FM Scanner 4 .12 channels 79.00(n.c. 61.7611.00 Hy-Gain 12AVO 20/15110m vertical 43.0012.00) Sound Air 008 8 channel FM monitor 69.001n.c. DM81 703kHz-250MHz dip meter Station log books 1.961 50 Hy-Gain 14AVO 40-10m vertical 60.0012.03) Sound Air M161 16 channel FM monitor ss.00tn.c. 12BY7A driver valves 2.751 .50 Hy-Gain 18AVT/WB 80-10m vertical 87.0012.50) MF081 Marine or Amateur +3 FM broad. 86.00(n.c. 6146B/52001A P.A. valves 8.701 50 HF5 90-10m vertical 200 watts 48.0042 00) BEARCAT 220FB VHF/UHF 258.00)n.c. 8.96) .50 Radial Kit for HP5 28.0012.00) SX200 VHF/UHF. New stock lust arrived! 240.01Xn.c. 6JS6C P.A. Valves Matched pairs PL259 plugs .83 (n.c. Sagant EL4OX 80 40 Balun fed dipole 179'1 36.0011.531 SR9 Tuneable 144-148 or 156- 162MHz 45.001n.c. PL259 reducers .17(n.c. Jaybeam TB3 HF 3 element Tribander 167.9014.50) AR22 2m FM pocket synthesized handheld 83.001n.c. .001 .10 Jaybeam.VR3 HF Vertical Triband 42.5013.00) AR22 flexible antenna 3.001n.c. 50239 chassis sockets PL259 joiners .861 .10 Western DX5V 5-band 89.0013.00) MOBILE AERIALS N. Plugs. Silver plated UR67 2.001n.e. DENTRON ASP201 2m ;- wave with base 3.6011.25 N. Plugs. Silver plated UR43 2.001n.c. ML425009 6 band 160-10m 2kW linear 696.00(n.c.) 9.2512.00 ASP2009 2 5/8th wave with base 4 pin rnic plugs .85( .10 Clipperton•L 6 hand 160-10m 2kW linear 459.00In.c.) ASP3009 2m 5/81h wave with base 9.7512.00 3 pin mic plugs .864 .10 DTR-1200L 5 band 80 10m 1-2JcW linear t . b. a . I n.c.) ASP462 70cm co-linear with base 8.3511.25 6 pin mic plugs (FDK 750) 1.00( .10 GLA-1000B 5 band 80-10m IkW linear 295.001n.c.) Magnetic base adaptor 8.501 .75 3 pin chassic socket .1351 .10 DT11.3KA 1-8 -30MHz ATU/2kW t . b. a . I n.c.) ASP677 2m 5/8th wave 14.95(2.00 4 pin chassis socket .85( .10 MT-3000A I -13-30MHz ATU/3kW 275.00In.c.) 17.95(1.25 ASP657 70cm co-linear BNC plugs (bayonet) .901 .05 AT-1K 1.8 -30MHz ATU/1kW 99.00In.c.) ASPM125 27MH: wave 18.60(2.00 Pen Cell Ni -cads tHP7 size) 1.20(.05 HF200A 80-10m transceiver 100W AC PSU 39'3.01Xn.c.I Magnetic base adaptor 8.501 .75 Cigar lighter plugs .664 .10 Spare set of 050A tubes 25.1313M.c.1 ASP no how boot mount adaptor 3.75( .50 UR67 cable 5052 per metre A* .10 All band Doublet 1.8-30MHz + 47057 feeder 22.6012.001 13.0012.03 2NE 2m 7/8th mobile whip UR43 cable 50f2 per metre .231 .05 ADONIS MICROPHONES RGRVI Baso for above aerial 3.601 .75 5 core rotator cable per metre .301.05 GSS Heavy duty gutter/boot mount 3.151 .50 AM202G Mobile safety mic 20.96(n.c.) 13L4OX balun 5011 11.281.35 MB5 Magnetic mount with 5rn coax 7.9611.00 AM202S Mobile safety mile 20.96(n.c.) 3 core rotator cable. Per metre .221.051 IOSE 28MHz whip 1-72m long 11.5011.25 AM202H Mobile safety mic 29.00(n.c.) Ferrite rings 1r diameter .351.05 AM502G Base station compressor mic 39.00(n.c.) 15SE 21MHz whip 1-72m long 11.6011.25 Mosley aerial insulators .301.05 20SE 14MHz whip 1-72m long 13.80(1.25 AM802G Base station compressor mic 59.00(nic.) KX2 SWL aerial tuner 0-5-30MHz 29.8041.50 SEM WEL2 PROFESSIONAL POWER/S WR METERS APM1 Audio Peak and notch filter 33.0011.00 49.951n.c. 2m power amplifier/pre-amplifier 5/30W 50.00(1.03) SP200 1-8-160MHz 20W-203W-1kW HP3A TVI high pass filter 'UHF TV.) 3.601 .50 09.951n.c. 2m power amplifier/pre-amplifier 16/50W 66.70)1.501 SP300 1.8-500MHz 20W-200W -1kW Drake TV3300 LP Low Pass Filter 18.4011.20 2m power amplifieripre-amplifier 16/100W 126.60(1.501 SP400 130-500N1H: 5W 20W -150W Shure 4440 high Impedance desk mic 27.5011.50 2m converter 23.00( .35) SHORT WAVE LISTENER AERIALS Shure 201 high impedance hand mic 12.5011.00 2m Auto switching pre-amplifier 21.731 .35) 3-30MHz Inverted ''L" 9.9511.00 Trio HCM10 Digital World Clock ES.2011.50

O M FLIC) TS830S £639.00..\ f I Ci R1000 £85.00 C. TR9000 £345.00

The receiver that revolutionised short w ave 115E001(19 An all mode 2 metre transceiver that serves the dual roll A brand new model having all nine bands fitted and pro y01133 band coverage 2001i1-1z to 30MHz SSB CW 'AM• uf mobile and base station Features include digital viding 200 watts input SSB.'C W Built-in 230V ac supo Both digital and analogue readouts are provided readout, 121 or 25kHz steps in FM, five memories band ly, 61468 tubes and full digital and analogue display together with 233V or 12V de operanon facilities Trio \scanning and a tot motel Send for colu....ert rrafler Plus a really comprehensive variable selectivity and engineering at its best and at a very competitive price / r\ sr h filtering system The DX-ers dream MAIL ORDER-FASTEST IN THE BUSINESS PLUS FREE INSURANCE ON ALL GOODS DESPATCHED. (Tel: 0702 206835) We have probably the busiest mail order department in the country. From the time the mail arrives at 8.30 a.m. until 5.30 when the mail vans arrive, our team of packing ladies are busy despatching your orders. We know how anxious you are to receive your new equipment that's why we have tried to build up the service that we ourselves would like to receive. So wherever you are in the U.K. you can choose your equipment from the comfort of your home with the knowledge that your order will be given top priority, packed safely with free insurance and despatched immediately to you. If you have a Barclaycard or Access Card, then simply telephone us your number. Alternatively, payment can be made by post in the foirn of cheque, postal order etc, made payable to Waters & Stanton. For your added convenience a special mail order slip is attached below. Please write clearly- we're pretty good at most things but useless with crystal balls!

M AIL O R DE R SLIP to: W aters Et Stanton Electronics, W arren House, M ain Roa d, Hoc kley, Essex. (E-C. W ed. 1.00 p m) Name Goods required Address

Please rush me the above. Cheque enclosed for £ Please charge to credit card No.

RADIO COM MUNICATION June 1981 501 TEURELeCTROMICS UK • Your number one source \e/ for YAESU Yi SEN Yec

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...... , Id á s • d .. . . . 11 1 0 # 1 T-101ZD

naI Now from YAESU cornes the latest version of the renowned FT-101 - AM/ FM option, notch filter, audio peak filter, variable bandwidth - UNBEATABLE VALUE.

mo, FT-480R High technology all-mode 2 metre mobile FT-707 All solid-state HF mobile transceiver

The most advanced 2 metre mobile available today- USB, LSB, FM, CVV full The definitive HF mobile rig, digitaLvariable IF scanning with priority channel, 4 memory bandwidth, 100 watts PEP SSB. AM, CW (pictured channels, dual synthesized VFO system here with 12 channel memory VFO

As factory appointed FT-707 In base distributors we offer station format "' you- widest choice, "'""r e • ' largest stocks,quickest deal and fast sure . . e ...... service right through- •

af t; l b -0

Here we show the 707 together c.] with the matching FP-707 PSU FC-707 ATU and FV- 707 DM Access or attractive VFO memory H.P terms readily available for on-the • spot transactions. For full details of these new and exciting models, send today for the latest YAESU CATALOGUE Full demonstration and LEAFLETS. All you need to do to obtain the latest information about these exciting j facilities. \e/ developments from the world's No. 1 manufacturer of amateur radio equipment is to send 36p in [ 'C stamps and as an added bonus you will get our credit voucher value £3.60 p — a 10to 1 winning Free Securicor delivery. offer. FL-2100Z High power all band HF linear FRG-7700 Synthesized general coverage receiver

The very latest in receiver technology from YAESU. Conservatively rated at 1200 W PEP input, the Receives USB, LSB, CVV and FM- memory option \.. new WARC model incorporates all the new bands \,... with 12 channels and automatic band selection. .)

FT-902DM Competition grade HF transceiver The YAESU world famous pace-setter with the acknowledged unbeatable reputation 160 thru 10 metres including the new WARC bands. All- mode capability, SSB, CVV, AM, FSK and FM transmit and receive, Teamed

with the FTV - 901R transverter coverage extends to 144 & 430 MHz

FT-225RD Deluxe 2 metre base station FT-207R I 202R s iegiuto. FT-202R 2 metre hand-held Ultra compact lightweight (400g) FM hand-held lwatt 6 channel, rugged and reliable -many thousands in use

FT-207R Synthesized The tried and proven all- mode 225RD has a very comprenensive 2 metre hand-held specification including memory 400 channels on option, variable power output and DC operation 144-146 MHz Memory \ •for portable working. \ t2ack-up, 2 5watt output.

AGENTS NORTH WEST - THANET ELECTRONICS LTD. GORDON. G3LECI. WHERE TO FIND US KNUTSFORD 10566)4040 WALES Et WEST-ROSS CLARE. GW3N WS. GWENT 10633188o 146 FT-290R FRo•••1 •40.2 ,14 , we•C /..10 till •••,027- r• Ram 00,1•10 4 CAS7 EAST ANGLIA -A MATEUR ELECTRONICS UK EAST ANGLIA. LI cmere•--t, DR 7 THIRST ITIM) G4CTT, NOR WICH 08925 866 FiC AC. su aF7 NORTH EAST NORTH EAST AMATEUR RADIO. DARLINGTON MS 66869 SOUTH EAST AMATEUR ELECTRONICS, UK KENT KEN McINNES. G3FTE. THANET MI « 7912n 6 Amateur Electronics UK

7rie - 51(09 IC 3 retrI.J2I: 508-516 Alum Rock Road. Birmingham 8 FRO•••4 4.127- og ••11.7

Telephone: 021-3271497 or 021-327 6313 A44, 8000 dl RcK W E HAVE 4J. exC1161.1 »ir Telex: 337045 PARI•OMG FAciL.Tierà `%. 014 ouR etop Opening hours: 9.30 to 5.30 Tues. to Sat. FORÍCouprt continuous- CLOSED oil day Monday.

RADIO COM MUNICATION June 1981 !-.103 c swag' rebus - r,s9oo - VAESU %Ian g¶e.o7;80.;. ..p..41 nand 94setn . 1114. O0 00( FtFe 10 10712 160 l ee el. sasut ers F741 121 Fi 690 00 639 00 'emote VFO 68 Fl 1012'20 t94 oo coo, 92 00 TRIO 160 - 10.9 taRa toan e m m .02 00 ,0600 o 501 eV:27'01:22 is eos too 10m o adsc e . 9 ban e grnipeo...60. 1 e1,:i.odi.....,,f1,...1,%.«,74ic:...,..... to6 00 3300 0 SCII 01 107M ye() no D e e vf 0 e.66 memeney 16300 11501 97 15 Al 730 AP band Al LI Faro rntein 76 4S 10S0i 10 700 1P 10 1E ze. 8 ‘ P .44 .0:1100: Fl 1°1 SP 230 Erlienag «ease/ und 0 500 26 15 OF G 230 0.9 Impeency remote connone 5750 isles :00 7; 7 ' 1;.:‘.7,17 :1,7 141S ca;r: YK Bac Boo pu C . IRM 7760 49 1 00 YK183CR 261 .4 CPI seer tie 00 404 00 F4sei:viii0V077PleV e‘ *Mensal spew ..° cae.c4 89 70 11501 23 OD 10 IS 130S 8 Dena 700 W (MO 2)00 40 +zee tibo, oust 07 c w12 ee....":777.0,73:::::i.e'e .07 15 1309 Strand 20 . pep ,725 1.001 ¶8 60 7530 0 001 ARF me. we il 10 7 0,... ,0 *265 lO 50011 120 170 200 8e De()%6070 Me 15 130v 500 esor.:,1..0r,f.e..t 70.,7„,.‘10 FI7 7,10, 90 7289 1.03' AM Me 100 M ete mourn Ice T5120'130 6 IS 1064 2 60' s111 SP ¶ 20 Bese Slabo6 eybee6.0 sea.... 500 des' nee c,ancelsdo il 707.107 00 ASE 00 85 3 001 M 35 500 pen Me mel me F1 707/ 107 Al 130 100 Ni adlena tune. 74 75 0 001 eta 36 579 00 PS 70 AC yarns suPPIS TS 120S' 130V 80- 10. 8 Dand 1...... - me P. 914 37 109 00 PS 10 A C POR M Ne e TS 1205,130S so . 10.. 8 w ee i.ân ee er • R.9hi w 24 tb 501 107 5 sow M AS 0406sn asPree aesa1 see . 23Cèdeou...._,100:„.. ei:,1"2:9,:t.cii.e.Ps fe.F1 186 03 1380 F I 701 3$0 tu 751 FP 707 1495 M C 50 2011 'P " Ore rne epN ee En 699707 F 0 ks 71 70 7 .810 MG 3SS F ne n6CM48,08e SOK e6pnevnce 18 40 03 751 f C 707 Metal meta MC 300 6,st «emcee. ea «v., ,BaeaarK8 /30 00 Fs 7070Fe rt ne N180 001 S e 7 30 6 H F 1. Pess 1.ne. 1 5W 16 W M 2 IS 7706 20" 70"'' ae mode 345 00 32 20 517i .60 - t1). 1200 9.6 sneer SP /0 Eg an» sCe36M une FL 21002 ohm REEREREE m 1R 9000 2fn rees esee druernode 265 0 • low 744 55 166 04 - Lew 11aMteet rii 7 900 2. F 74 sern erted900 nseae0 7 SIN 49 45 11 00. FF 50 1 W ed dab w ant I 0 9 am. Bemo.z., in 7109 a 12 amp() C 11/5 1101P OIRF6 Il74 IR 2300 2r, n F M pirene;wsels. 30.40017. 2309 a c 4 amp 0 succ. 6 90 0901 ot. 4.7« MG 2 Mor e nuous:" JT; 2302 0 'VD 2)00 FP 4 9B 2300 +se 0 5 30 Mbir ceenenurycaton 43 70 F517 RA , Fle ws lee* enter,. Le1es1 en coy recur.. 6Cen Yetin, 172S M O, FRG 7 114 2400 2rd F IA seme eed ',epe e tS0 0 501 FRG 7700 ataWe .4.16 St 1 Base Stand and W es crepe, 2,6F M Syeenteeseel nemele8 1426 001 ERG 77 00 M Nona last c.6414e1,603 Fl 20 7 BG S 12Y a‘x,,, ewe.. i I ern SC 3 S e cadIsis3 Fine 28 500 - Ncad 230+ ey e. SO' FT 207 76 45 0 501 74C 2 08 21 Sim m 604119 pan, [Mete me Spre d. .1 wee. ecs 10 35 10 75' NC 9 R 1000 Gen coe,8e. «...•••••• 21 65 '0 is, NBP 9 129P S U 1o7FT 207 SP 100 E .14.11 sp.. . en Neat; pace enanatro adapte ea° tO 751 PA 7 .45 4 8006086, 714 srnins9setsmuencue aBeaao.B., FBA I 1.44teseo 2309 a c 80.05.60119 MS 5 G er.' sead eonee FT 480F1 .0 10 0 9141 Peon won) tent c.c.. M K VHF UHF EQUIPMENT m 1001.X 7.m F M vr1,,,sell SPI 71A1 M sy1616Dvsannencl6M0 M 750E 2. SynIneseed mun mode mo6ne

EYPAncinn 70 CM imnsyene,10, 44 1500 S e case S erer - nuctoonone PS 750 A C po et 'w e . 61 7Bac 23044e tee e w e. aEa STANDARD (70 con) 230. a c ev e C76 Ord i 'A 162.68n6.0m Cal ends.; head 69 Need per le lc 2E C1.8 1..auet . Cast For . pace 1o. IC 2E 1.:1411 Moo . nouns . c, é#1. En-pry top e caul . IC 7E G P8 78 , Ow use» asesies Se Need ed. let ,C 2E

MORSE EQUIPMENT 7140 Msynin evid mo de 110..

27.4F serdevsed (2Sw• 14« 107 U0,00.^ ser IC 2+0 2m .ymen.,sedem emode itOor M K 704 Squeeze P.94 . C 255E IC 260E 214 meenode base ea.). EKEKN1 121 12 Emu')Matcrung sule tone ..ore e IC 25 1E 214 SSO peat. leflANceyef ce, Irerne. EK 150 Etecuone xeris C 202 0 20 ansa peer sues/ ict LC 720 POWER SUPPLIES - offlwes.efflgrne plOte am6 IC 720 rC PS15 Su es«) Mc is, e zstaso ,c roe a A.mp GOMe mauS 4 Amp 12,.. SU 0 2S 10001 6 4.0 Co . . .vs 6 eso +79 P S U ST All ON ACCESSORIES 51 00 10 751 12 AMP C enno085 17 eso.'79P S O 6466m I MN zsoo rbl 24 AR%) Conun eus 74 enc. IN P S U à 50 10251 no Cr4 600 10301 Rime melee Non pee seer - le ocrid..ad 24 00 P) 301 SWR - POWER METERS roHP I 3* 30 B e nny toad 3503 40301 YIN 3 Iron Miee S W 1104 Dan. (1 8 - 150 14141 100 .0 .. .1oad 000/ Mt' 1300 0 001 Load 15007101:1 SP 200 W M: {1 6 - 150 Mt18 29 90 (1 el se 11001 SP 400 Weil 1130 - S00 66471 Gee 670 4 0.940 0 8 - 15o 74711.1 ooss P. .. 020 10 OS1

SP 300 Welt 0 8 - 500 SINN 0 00 40 20f 0 20 10021 CN 610 04.4 1140 - ea e.:1c,,,,,P,,,,,,, 0 la 10 021 .00 10 10) MICROPHONES Mte 202 5 M om% 462 on saMei mC W A 2021i0 Ad en dead end se . n. • 1.19 . 0.6

MM ?02t1 &pony sa1.1 11.

AM 502 A essco esesso7 n. AM 607 M on, ccm pessy m c O P s

P M 9.0 Oeme,nfrà ,,,d 80. se er To order any of the above items simply write, enclosing a cheque, or phone your credit card number to: Bredhurst 00C M:01104 High St, Handcross, W. Sussex. Tel. 0444 400786

504 RADIO COMMUNICATION June 1981 PA° 2

CARRIAGE C-2E £159 inC.V e 8« • Fully synthesized - covering 144-145 995 In skt-iz steps • 1 5W power output with 9V battery as supplied • Optional 6V or 12V packs tot lower

or higher power • BNC antenna output soc ket tor he lical or external antenna

Weight - only grams with • supplied battery pack and helical• .

Send/battery indicator - indicates

tra nsmit until time tor battery rec harge • Duplex/Simplex switch - Sir LOW

po wer SvelCh • Optional external speaker microphone available now • Full 12 months guarantee tor all rigs bought trom eiredhurst Electronics TR-7800 FEATURES INCLUDE • 15 Muititunction channels. selectable with rotary

control • Priority Alert Audible warning plus immediate

operate switch • Internal battery backup bon all memories Full coverage 144.00 to -145 995MHz in either • 5kHz or 25kHz steps Front panel keyboard 01 frequency seiection, scan • control and memory programming • Frequency readout and channel in LED display • 25W power output with HI/LOW power switch

• Overvoltage Crowbar protection •Short circuit proot • Foldback current limit • Regulation better than

• Fused Output protection •Thermal overload .1)0P protection The popular 101Z and 101Z0 are now better than ever Ce01./tuous Re.; Pme tC4r04941 4 A410 £27.95 being lilted with FM,audio peak/notch 1ilter,att me new AMP £44.95 12 001 bands and an improved tront end 12 AUP £69.00 n• °) Am° when you buy your 101Z Irom Brednurst you get a .1110 £92. 00 00) tree microphone and Coding Ian A new wave meter designed to meet the 101Z £529 inc VAT requirements o12 metre 101ZD £599 inc VAT operators Frequency range 130MHz to 500M1 ex Tel. 0444 400786

RADIO COMMUNICATION June 1981 505 iwAM ATEUR RADIO EXCH ANGE Here at Amateur Radio Exchange we believe in choice, because only if you, the customer, can see and try the widest possible range of equipment side by side will you be sure that what you're buying really suits you. Go to the Trio dealer, and he'll tell you that Trio is best . . . the lcom man will push his range exclusively . . . and so on.

FT-707 FT101 Mk Ill The ultimate in HF mobile The tried and tested Yaesu HF base transceivers from Yaesu. All the station, now with audio peak filter and new bands, and all the latest reject notch filter as standard, and

technology. —71 choice of AM or FM. £529 _ . FT1011 from £499 Jim. VAT and FREE le • é' FT10110 from £519 cooling fan Et mic • • • azuarrieeti .

FT-200RIFT-708R FRG-7700 Yaesu's marvellous new hand-held Yaesu's latest for either 2m or 70cm operation. receiver with FM Its LCD display (with night-lamp right across the feature) is coupled to a 4-bit band now microprocessor giving 10 offers yet more memories, up/down scanning in optional extras. 25 or 50kc steps (manual or auto) Memory facility .. . plus memory scan and scanning Aerial tuning unit . . between two desired frequencies, and no less than four converters. priority channel with search-back, keyboard entry allowing split A. 118-130MHz, 130-140MHz, 140-150MHz frequency for non-standard 8. 118-140MHz, 140-150MHz, 50- 60MHz repeaters... and lots more. C. 140 150MHz, 150 160MHz, 160 170MHz PHONE FOR PRICE D. 118-130MHz, 140-150MHz, 70 80MHz

Basic receiver £299 Inc. VAT and FREE Heliscan aerial worth £15

IC-720A TS-830S ,- , A A, Another Trio/Kenwood corn's superb new HF rig - Ina .1 with general coverage le development of an existing 111 receive 100kc 30MHz plus best-seller. ... the TS-e0 W gives way to the TS-830S, transmit facility across its I IF entire range for commercial tFhsehnifetwelnds, purposes e> rn'Crtychw:itletler" 111 111.1 tc £795 inc.VAT £625 inc. VAT and free mic.

FRG-7 Still the finest value-for- I el e/ el‘i!iCeitj el4II money communications N receiver on the market at esli>" Now in stock only A full range of Wood Et Douglas £185 inc. VAT and free kits and modules Hellscan aerial worth £15

TR-9500 Trio/Kenwood's new UHF FT-480RIFT-78OR all-mode mobile transceiver in the popular TR-9300 format, with full Yaesu's pace-setting 10MHz cover from 43) to 440, and mobile format now incorporating such features as five memories and priority channel, memory available for either 2m or scan, green LED display, etc. 70cm use. PHONE FOR PRICE. FT-48011 f359 .1 Inc. VAT and Fr.noR £395 FREE power supply II Em ma imm LICENCED CREDIT BROKERS * Ask for written quotation Prices are correct as we go to press, but owing to currency INSTANT HP AND 6-MONTHS NO-INTEREST HP TERMS BUICURMIIRD fluctuations, etc, may vary by publication date. Please phone for AVAILABLE FOR LICENCED AMATEURS AND latest information. BANK/CREDIT CARD HOLDERS Crean card sa/es by telephone All prices include VAT, but p&p/carriage are extra.

506 RADIO COM MUNICATION June 1981 -AM ATEUR RADIO EXCH ANGE But here you will find ALL the leading makes . . . YAESU, ICO M, TRIO/KEN WOOD, DRAKE, COLLINS etc . . . so Brenda (G8SXY) and Bernie (G4A0G) invite you to make your choice, either in the shop, or on our stand at major Rallies through the year. At Ealing there's sometimes another choice too . . . mostly you'll be offered a cup of Brenda's coffee, but around 4 o'clock it might well be a cup of tea!

THE FANTASTIC NEW SONY ICF-2001

At last, from one of the world's electronics giants, a real HF communications receiver . and the very first with keyboard frequency entry . .. yet so compact you can slip it in your briefcase. I Super selectivity and sensitivity right across YAESU's its range. AM/SSB LATEST ... the new all-mode 2m portable FT-290 1 150kc to 30MHz and FM 76MHz to 108MHz. And all for an So many features * 10 memories * Memory scan * 2 VFOs * Band amazingly low price scan * Clarifier * FM/LSB/USB/C W * LCD readout * Real 1 of ¡List S-meter * Priority channel * 2-5w out £159.00 inc. VAT. £229

PCS-3000 IC-730 The first mobile HF Azden's pace-setting transceiver on the "-eil I I 111 zliaz 7!. new 2m mobile giving •.. market with two VF0s. P' t 25w out, with 25kc or Also featuring Band 1 12-5kc shift and 8 - Pass tuning and giving _ memories . out 100W. 0 (1) all for only £199 Inc VAT £549 inc. VAT

Service with a Smile Components Galore Our new Servicing Centre just across the road from the main shop also keeps in stock a vast array of those bits and pieces the en- thusiast finds it so difficult to get hold of for building or modify- ing his own gear. You name it—we've probably got it in stock. And, if we haven't, we'll order it for you. Capacitors—all preferred values 1 Ceramic plate IPF 47.000PF. Electrolytics 4.1.7 I,000P1'. Tantalum Bead I.51: 221.d: Resistors—all preferred values Integrated Circuits—C M OS —Transistors—Rectifiers—Voltage regu- lators etc. etc. Up the Pole Of particular interest at the moment, since erecting them makes such a nice outdoor job for the summer, are aerials and all their ancillary items . . . Aluminium tubing, 1 and 2 inch—Stand-off brackets—Chimney lashing kits—Guy ropes and tensioners— Mast clamps—Cable grips—Rotators—Rotator bearings—Diapole centres—Insulators —Antenna wire—Baluns—Earthing rods—Plugs and sockets etc,

Closed Wednesday, but use our 24-hour Ansafone service. 2 NORTHFIELD ROAD, EALING, LONDON, W13 9SY. Tel: 01-579 5311 So easy for Overseas visitors— North fields is just seven stops from Heathrow on the Piccadilly Line

RADIO COM MUNICATION June 1981 507 RadioShack Ltd for Amateur Radio TS130S 8 band 200W pep mobile R. L. DRAKE PRODUCTS TRIO EQUIPMENT transceiver 491.06 5.00 Inc. TS130V 8 band 20W pep mobile trans. MC50 Deluxe dual impedance desk Model Desenpmen VAT Carr. ceiver 404.34 5.00 microphone 24.15 1.50 TA-710R-7 Transceiver /Gen. Cou DFC230 Digital frequency remote con- MC35S First microphone 50k im- Receiver Digital £1035.00 5.00 troller. Four memories etc 16313 1.50 pedance 13.80 1.00 PS-7 Power Supply 120/240v for TS120V 80 10m 20W pep mobile MC3OS First microphone 50flohen im• TR•7 207.00 5.00 transceiver 347.30 5.00 pedance 13.80 1.00 PS-75 Sideband Duty P.S.U. for T1120 200W pop linear for TS120V 128.80 5.00 LF30A HF lowpass filter. IkW rating 18.40 1.00 TR-7 120/240v 138.00 5.00 MB100 Mobile mount for 15120/130 R 0300 IkW oilfilled dummy load, 48.30 1.50 RV-7 Remote V.F.O. for TR-7 132.26 2.00 series 17.26 1.00 TS770E 2m/70cm all mode dual band MS-7 Matching Speaker for TR 7 YK88C 500Hz CW filter 26.46 0.50 transceiver. European and R-7 29.90 2.00 YK88CN 270Hz CW filter 28.76 repeater shifts 730.25 5.00 0.50 R-7/DR-7 Digital Receiver 0 30MHz, 989.00 5.00 YKE03SN 1 -8kHz SSB filter 25.30 0.50 SP70 External speaker unit for all SL-300 CW Filter for TR.7 and R 7 VF0120 External VFO 89.70 5.00 TS700 series 18.40 1.00 13001-1:1 39.10 0.50 SPI20 Base station external speaker 189000 2m synthesised multimode SL-500 CW Filter for TA-7 and R-7 unit 26.30 1.25 mobile/fixed station 1500Hz) 39.10 0.50 SP40 New mobile speaker unit 26.89 1.50 transceiver 345.00 5.00 SL-1600 SSD/RTTY Filter for TM- ATI30 100W antenna tuner including PS20 AC power supply for 189000 44.85 5.00 7/ A-7 (1800Hz) 39.10 0.50 new amateur bands 72.89 1.50 809 Base plinth for TR9000 32.20 5.00 SL-4003 AM Filter for R.7 Receiver PS20 AC power supply for TS120/ IR 7800 2m FM synthesised (4003Hz1 39.10 0.50 130V 44.86 5.00 mobile/fixed station 25W SL-6000 AM Filler for TR-7 end R-7 PS30 AC power supply for TS120/ transceiver 268.00 5.00 16001-121 39.10 0.50 130S 86.10 5.00 SP40 Mobile speaker unit for AUX -7 Range Prog. board and 1 MA5 New Trio 5 band mobile aerial TR7800. TR9000 and TR8400 26 89 1.50 Receive module 32.20 1.00 system. Absolutely complete. 74.75 5.00 RM76 Microprocessor control unit RAM-7 Range receive modules for TL922 160 10 metre 2kW linear. for TR7600/7625 60.95 1.50 Aux-71501>Hz) 5.75 0.50 3 5002 tubes included 5.00 182300 2m FM synthesised portable 586.75 RTM-7 Range tcve. modules for transceiver 166.75 5.00 Aux 71500kHzI 5.75 0.50 V82300 ICAN amplifier for TR2300. 49.45 1.50 TELEX COM MUNICATIONS INC. NB-7 Noise Blanker for TR-7 66.24 1.00 MB2 Mobile mount for TR2300 and NB-7A Noise Blanker for R• 7 Underchin headphones 6.21 1.00 VB2300 17 25 1.00 HFC-91 Receiver 66.24 1.00 Underchin headphones 9.20 1.00 RA1 Rubber flexible antenna for HMC-2 FA-7 Fan for TR.7 and PS.7 20.70 2.03 HIC-2 Twin Receiver headphones 14.72 100 182300 or TR2203GX 6.90 0.50 M MK-7 Mobile mounting kit for TR .7 34.60 2.00 PS1200 AC power unit and charger for BOOM MICROPHONE HEADSETS MN-7 ATU/ RE Wattmeter. TR2300/323)/2200 INon Trio CEI-88 3 -2 .20 ohms with power 160 10m 1250w) 124.20 5.00 item) 29.50 1.50 41.40 2.00 MN-2700 ATU/RF Wattmeter 160 10m microphone TA 2400 2m FM synthesised handheld 198.95 5.00 CM-1=0S 3.2 20 ohms Single Head- 12kwl 207.00 5.00 SMC24 External mic/speaker for 2400 13.80 1.00 phone Hi-impedance WH-7 RF Wattmeter /VSWR Bridge ST1 Base stand and quick charger 43.70 1.50 microphone 36.80 2.03 IHF) 59.80 2.00 8C5 12V quick charger 17 25 1.50 SP-76 Speech Processor 79.35 2.00 DUAL MUFF HEADPHONES SC3 Soft carrying case. Includes CW-75 Electronic Keyer 59.80 2.00 2.00 belt hook 11.50 0.50 C-610 Dual Receiver magnetic 6.90 P-75 Phone patch 59.80 2.00 SWL-810 Dual Receiver magnetic 8.28 200 LH1 Hard leather holster type case 18.50 0.50 7804 Service Manual for TA-7 18.60 2.00 C-1210 Dynamic. foam padded 18.86 200 PB24 Spate battery pack and 7806 Service manual for R-7 18.50 2.00 C-1320 3.2 20 ohms Telex's Best 26.22. 200 charger lead 14.28 1.50 7037 TR.7 Service Kit 37.96 1.00 188400 70cm FM synthesised mobile MICROPHONES (battery powered/ L-76 Linear Amp 2kw 10 160es transceiver. 430 440MHz 279.00 5.00 11.96 2.00 with tubes (21 897.00 10.00 PROCO M 1 High Output PS10 Base stahon power supply for 17.95 2.00 3-5002 Tube for L-7E and L 75E 69.00 2.00 PROCO M 11 Variable gain TR8400 63.00 5.00 23.92 2.00 L-75E Linear Amp lkw 10 160m CB-73R Dynamic, noise cancelling 18 3200 70cm FM portable receiver. 3 25.30 200 with tube 111 549.70 5.00 C8-73S as above with 6-wire lead channels fitted 164.45 5.00 TV-42LP Low Pass Filter 100w 10.35 1.00 PB10 Pack of 10 NiCed batteries for TV-33001P Low Pass Filter 2kw 18.40 1.50 MACROTRONICS 182300/3200/2200 series 10.36 0.50 7073 Hand Microphone for TR-7 18.40 1.00 Pli 5.00 7077 Desk Microphone for TA-7 29.90 2.00 Spare power/charge lead for CM. « HAM Interface for TRS.80 230 00 TR2300/3200/2200 series 1.30 0.15 T tm DL-300 Dummy Load 330w 20.70 1.00 1M-800 DereRTTY and moise for 81000 Synthesised 203kHz 30MHz 362.25 5.00 CIL-1000 Dummy Load 1030w ..... 37.95 2.00 receiver. Price includes dc kit TM-650 Deluxe RTTY and morse for CS-7 Remote control ant. switch 5 fitted 285.20 5.00 328.91 5.00 way 17 linel 115.00 5.00 PET SP100 External speaker unit 32. 95 1.00 B-1000 Balen for MN-7 and MN-2700 88•1 RITTY Alter Editor for TM- Matching aerial tuner. See Electra Sketch (Editor end 41 20.70 1.00 ESK KX2 in Mizuho section 26.45 1 50 Animations Compiled 9.90 1.00 Manuals Spare Operating Manuals 6.00 I 00 HCIO Digital station world time Interface 11-7/TR-7 connecting cable 20.70 1.00 clock 56.20 1.50 AK-75 Multiband Antenna 23.00 2.00 VIBROPLEX HS5 Deluxe headphones for all AA-75 Antenna Insulator Kit 2.30 0.50 Trio equipment 21.85 0.75 Presentation Super de luxe Semi HS-75 Headset 995.00 100 HS4 Economy headphones 10.35 0.75 Automatic Bug Keys 89.70 200 TS830S 160 10m transceiver with the Original De Luxe Semi AUIOMElliC Bug COM MERCIAL SPECIFICATION RECEIVERS AND new bands. Successor to the Keys 59.80 200 TRANSCEIVERS TS820 E39.52 5.00 Original Standard Semi Automatic R4245 Commercial Specification VF0230 Digital VFO with memories Bug Keys 46.00 200 Receiver 2129.00 5.00 and digital readout 194.45 5.00 Lightning De luxe Semi Automatic Bug 184310 Commercial Specification AT230 All band ATU and power Keys 59.80 200 Transceiver 2294.25 5.00 meter. Matches TS830S 106.72 1.50 Lightning Standard Semi Automatic RR-3 Marine Specification Receiver 1380.00 5.00 S P230 External speaker unit with Bug Keys TAM Marine Transceiver MF and 46.00 2.00 switched filters 33.14 1.50 Champion Semi Automatic Bug Keys 43.70 2.00 HF 1265.00 5.00 052 Optional dc pack for TS830S 39.93 1.50 Vibto-Kayer De luxe Paddle for Electronic MRT55C VHF 55 Channel 549.70 5.00 DFC230 Digital frequency remote con. Keyer 69.80 2.00 Cabinet V for RI1.3, 84245 and troller. Foul' memories, etc 163.13 1 513 Vibro-Keyer Standard Paddle for Sec- TR4310 168.70 5.00 'NB The DEC 230 will drive the ironic Keyer 2.00 MN4438 General coverage tuner 239.20 5.00 46.00 TS830/ 130 or TS120 series rigs ENDS OF LINES Whast stocks last/ YK88C 500Hz CW filter 26.45 0.50 ADVANCED ELECTRONIC SPR-4 Programmable Receiver 345.00 5.00 YK88CN 270Hz CW filter e3.7s 0.50 DC-PC DC Power Cord for SPR-4 3.46 1.00 APPLICATIONS SM220 Station monitor scope 197.80 4.50 XTAL Accessory Range Crystals 6.44 0.50 858 Panoramic display for 1S830/ FL-500 500Hz CW Filter for RAC 39.10 0.50 M M-1 Morsematic Special Keyer . 124.20 2.00 180/820 series 48.30 0.50 FL-4000 4000Hz AM Filter for 14.4C 39.10 0.50 MK-1 Keyer 49.46 1,00 855 Scan board as above for FL.6000 6000Hz AM Filter for R-4C 39.10 0.50 ISO-144 2m Antenna 34.50 2.00 15520 series 48.30 0.50 MS-4 Matching speaker for 4 line 29.90 2.00 8820 The ultimate amateur band AC-4 DSU for TA-4/1 4X Series.. 60.00 5.00 receiver 690.00 5.00 TEN -TEC EQUIPMENT DC-4 AC/DC PSU for TR 4 84.50 5.00 500Hz CW filter 58.65 0.50 FF-1 Fixed Frequency Control tor YG455C TRANSCE IVE RS YG455CN 250Hz CW filter 60,95 0.50 TA-4 27.60 1.00 515 Argonaut, 5W. 3-5 30MHz 276.00 5.00 YG88A 6kHz AM filter 34.50 0.50 34-PNB Noise Blanker for TR-4C.. 69.00 1.00 646 Omni-D, Digital, Series C. TS180S 160 10m solid state trans RV-4C Remote VFO for TR-4C 92.00 5.00 SSEI/C W 1-8 30MHz 736.00 5.00 crime,. Digital memory sys- CW-MOD 500Hz CW Mod for TR.41C). 52.90 2.00 5706 Century/21. 70W. CS tem. 200W pep 679.65 5.00 RCS-4 5 Way Coax Remote Antenna 3.5 29MHz 240 volts 230.00 5.00 VF0180 Ex terrial VFO 96.60 1.50 Switch 84.50 2.03 SOO Delta, 200W. SSB/C W, SP180 External speaker unis with WV-4 VHF Wattmeter 100/ 1COOW 1-8 30MHz 469.20 5.00 high and low pass filters 36.80 1.50 20/200MHz 59.80 2.00 AT180 Matching 200W antenna tuner POWER SUPPLIES AA 10 2m Linear 1:10 Watts . 39.95 1.00 and powerful meter 95.45 5.00 210/E 115/230VAC. 13VOC. lA ... 27.60 200 1525 EM Encoder Microphone 34.50 1.00 YK88C 500Hz CW filter 26.45 0.50 280 117/230VAC. 13-5VDC. 18A 92.00 5.00 P5-3 6Amp 13-6 VDC Power Second SSS filter option Supply 69.00 5.00 YK88S 26.45 0.50 LINEAR AMPLIFIER SD-AUTO SD-240/120 Auto Trans P530 AC power supply for TS180S 85.10 5.00 444 Hercules. lkW with 115/230 former 19.95 3.03 VAC. Power Supply .. 920.00 10 00

508 RADIO COMMUNICATION June 1981 ACCESSORIES 8XY/2M Crossed 8 element yogi with BENCHER PRODUCTS 296A Crystal Calibrator 18.86 2.00 11 boom 28.40 208A Notch/C W Alter for Model 10XY/2M Crossed 10 element yogi with BY-1 Keyer Paddle (Black basel 29.75 515 29.90 2.00 1r boom 37.72 BY-2 Keyer Paddle 'Chrome basal . 37.95 212 Crystal, for Model 515, X6/2M/X12/ BY-3 Keyer Paddle 'Gold platedl... 92.00 29.0 295 MHz 3.45 0.50 70cm Dual band crossed yogi 38.52 ZA-1A Balun 3-5 30MHz for dipoles 12.65 213 Crystal, for Model 515, PMH/2C 2 way phasing harness for cir- ZA-2A Balun 14 30MHz for beam 29• 5 30 ,0MHz ...... 3.45 0.50 cular polarisation 747 antennas 13.80 215P Microphone, ceramic with 04/2M 4 element quad yogi 23.69 plug 18.40 2.00 136/2M 6 element quad yogi 31.40 HUSTLER ANTENNAS 215PC Microphone, ceramic with D5/2M Double 5 slot-fed vagi with 1" plug and coil cord 21.85 2.00 booms 20.12 AMATEUR ANTENNAS WITH MOUNTS 217 500Hz 8 pole Ladder Filter for 08/2M Double 8 slot-fed yogi with 1' 4- BTV 4-Band Trap Vertical 10 40m, 66.70 Models 545/506 36.80 1.00 booms 27.14 5- BTV 5-Band Trap Vertical 10 80m. 86.25 218 1 -13KHz 8 pole Ladder Filter SVMK/2M Mounting kit for vertical BBLM-144A 5/8 Wave 2m Magnetic. 17' for Models 545 / 546 36.80 1.00 polarisation for 2 slot-fed coax 28.75 219 250Hz 6 pole Ladder Filter for yogis 7.24 BBLT-144A 5/8 Wave 2m Trunk lip and Models 545/546 34.50 1.00 UGP/2M Un/pole and ground plane . 10.12 coax 26.45 2213 Antenna Tuner 58.80 2.00 H0/2M Mobile 'halo' head only 4.55 CGT -144 2m Colinear. Trunk lip and 243 Remote VFO for Models HM/2M Mobile 'halo' with 24" mast 5.40 coax 29.90 545/546 103.50 5.00 PMH2/2M 2 way phasing harness for two G6-14413 6db 2m Base Colinear 59,80 247 Antenna Tuner 43.70 2.00 2m aerials 9.89 G7-144 7db 2m Base Colinear 89.99 273 Crystal, for Model 570. PMH4/2M 4 way phasing harness for HT-144 "Hustleoff- 2m 5/8 wave 28-5 29.0 3.45 0.50 four 2m aerials 23.11 mobile 19.99 276 Crystal Calibrator for Model SFM 5/8 Wave 2m Magnetic and 570 16.86 1.00 70cm Antennas COW{ 22.99 277 Antenna Tuner/S WF' Bridge C8/ 70cm 8dB glass fibre «timar, SFS-144 5/8 Wave 2m Speedy Mount 15.99 for Model 570 57 50 2.00 omnidirectional 50.02 MONITOR ANTENNAS 2E2 250Hz 6 pole Ladder Filter for D8/70cm Double 8 slot-fed vagi with r DCX 40 700MHz Receiving Model 580 35.65 1.00 booms 20.70 Discone 13.80 283 Remote VFO for Model 580 112.70 2.00 PBM18 /70cm 18 element Parabeam yogi DCL Discone as above with 50' 286 500Hz 6 pole Ladder Filter for with I r boom 25.30 coax 20.70 Model 580 32.20 1.00 MB M48/ 70cm 48 element Multibeam vagi UHT-1 140 500MHz Unit Gain and 229 Noise Blanker for Model 580 29.90 1.00 with trombone mounting 28.75 15' coax 6.50 1140 DC Circuit Breaker for Models MBM88/70cm 88 element Multibeam yogi 545/546 and 580 4.60 1.00 with trombone mounting 39.33 ACCESSORIES 1150 Overvoltage Protector for 8XY /70cm Crossed 8 element yogi corn. BM-1 Bumper Mount 11.95 Models 262 Series 9.20 1.00 plots with phasing harness C-29 Stainless Steel Spring 7.95 1179 DC Circuit Breaker for Model and 'N' type connector 34.15 C• 32 Chrome Ball Mount 5.50 570 6.90 1.00 12XY/70cm Crossed 12 element yagi com- HLM Deluxe Trunk Lip Mount 11.95 plete with phasing harness M M-1 Universal Single Hole Mount e.ee KEY ERS and 'N' type connector 42.32 M M -3 Universal Single Hole Mount 645 Ultramatic, Dual Paddle 55.20 2.00 PMF42/70em 2 way phasing harness for two and coax 11.95 670 Single-Paddle Keyer 23.00 2.00 70cm yogis 8.51 00-1 Quick Disconnect Fitting 9.99 PMH4/70cm 4 way phasing harness for RSS-2 Resonator Impact Spring 4.95 ENDS OF LINES (whilst stocks last) four 70cm vagis ...... 18.05 SSM-1 Stainless Heavy Duty Ball and Spring 21.95 TRANSCEIVERS 23cm Antennes SSM-3 Stainless Heavy Duty Spring 10.95 544 Triton IV 200W. SSB/C W D15/1296 Double 15 slot-ted yogi with 3.5 30MHz with digital 'N' type connector 34.04 RESONATORS AND MASTS readout 399.86 5.00 PMH2/23cm 2 way phasing harness for two HM -10 10 metre Resonator 6.95 545 Omni-A. Analog. Series B. 23cm antennas 25.41 RM-10S 10 metre High Power SSB/C W. 1.8-30MHz 448.86 5.0) Resonator 11.95 RM-11 27MHz C8 Resonator 6.95 Mobile Antennae POWER SUPPLIES (when bought with Ten-Tee transceiver) RM -15 15 metre Resonator 6.94 252M 0/ E 115/230 VAC. 13VOC. 18A TAS 2M 5/8 wave glass fibre whp with 15.29 RM•15S 15 metre High Power for Omni 79.35 5.00 4 metres of coaxial cable. U5 70cm Colinear 5.6dEl with 4 Resonator 11.96 262M/E 230 VAC. 13VDC. 18A. 9.60 metres of coaxial cable.. 17.25 RM-20 20 metre Resonator deluxe with VOX (Tritonl 86.10 5.00 RM-20S 20 metre High Power Carriage on all the above Antennas - £5.00 14.49 ACCESSORIES Resonator 212 29.0 29-5 Crystal for Models RM-40 40 metre Resonator 11.50 RM.40S 40 metre High Power 540/544 3.45 0.50 HY -GAIN ANTENNAS 213 29. 5 30MHz Crystal for Resonator 15.99 Models 540/544 3.45 0.50 18HT 6 80m Venica1Tower .. . 258.75 RM-80 80 metre Resonator 12.60 240 160m Converter for Models 12AVQ 10.20m Trapped Vertical .. 48.50 RM-80S 80 metre High Power 540/544 57.50 2.00 14AVQ/WB 10 40m Trapped Vertical .... 60.37 Resonator 24.95 241 Crystal Oscillator for Models 184 VT/VVB 10-80m Trapped Vertical .... 87.40 MASTS 540/544 23.00 1.00 18V 10 -Kim Vertical 31.97 MO-1 Mast for Wing Mounting .... 14.95 249 Noise Blanker for Models TH6DXX 6 element beam for 10/15/20 235.75 MO-2 Mast for Bumper Mounting .. 14.95 540/544 18.40 1.00 TH3MK3 3 element beam for 10/15/20, 160.55 SF-2 2m 5/8 Antenna fits Hustler AC-4 SWR Meter Lower Power 6.90 1.00 TH3JR 3 element beam for 10/15/20. 130.52 Mounts 8.50 KR-5A Single-paddle keyer. TH2MK3 2 element beam for 10/15/20. 126.21 6 14VDC 25.30 2.00 CARRIAGE EXTRA. PLEASE CHECK FOR DETAILS H Y. GU AD 2 element quad for k0/15/ 20 194.35 KR-50 Ultramatic. dual paddle. 117 DB 10 15A 10 and 15m beam 132.25 VAC/6 VDC 57.50 2.00 2064 5 element 20m beam 235.75 COLLINS EQUIP MENT J BEA M ANTENNAS 20484 4 element 20m beam 178.25 203BA 3 element 20m beam 135.12 KWM.380 Amateur HF Transceiver... 1.794.00 10.00 4 metre Antennas 155BA 5 element 15m beam 135.12 KWM-380 OPTIONS 4Y/4M 4 element folded dipole yogi 15304 3 element 15rn beam 72.16 AC-3801 Norse Blanker 120.75 5.00 with boom 20.70 ir 10394 3 element lOrn beam 58.65 AC-3882 Speech Processor PMH2/4M 2 way phasing harness for two 10513A 5 element 10m beam 106.80 AC-3803 Control Interlace 82.80 2.00 4m yogis 12.19 402134 2 element 40m beam 18170 AC-3810 CW Filter. 500Hz 59.80 1.00 2 metre Antennas 511 Heavy duty spring 11.84 AC-3811 CW Filter. 250Hz 59.80 1.00 AC-3812 RTTY Filter. 1- 7kHz 59.80 1.00 DC1/WB Wide band discone 499 Flush body mount 11.84 1100 470MHz) 41.40 417 De luxe spring ...... 9.02 AC-3813 AM Filter. 5.0kHz ------36.80 1.00 LR1/2M Omnidirectional vertical gain 492 Miniature spring 4.60 KWM-380 ACCESSORIES colineer 24.15 AC-2801 Rack Mount 82.80 2.03 C5/2M 5d8 glass fibre colinear. omni- LA.1 Lightning arrestor 23.34 AC-2908 Blower Kit 120.75 2.00 directional 44.27 LA-2 In-Line Lightning arrestor 3.80 AC-2821 DC Standby Power Cable 33.35 2.00 5Y/2N1 5 element gelded dipole vagi BN-66 Ferrite balun 15.52 M M-280 Handheld Microphone 23.00 2.00 with 1- boom 11 .Z7 TELR EX 7856M 5 element beam for M M.281 Handheld Noise cancelling 8Y/2M 8 element folded dipole vagi 10/15/20 368.09 mie 27.60 2.00 with 1" bourn 14.45 S M.280 Desk Top Microphone 47.15 2.00 10Y/2M 10 element folded dipole 'long CDE ROTATORS SM.261 Desk Top Noise cancelling vagi' with ir boom and mie 51.75 2.00 trombone support 31.05 AR-20XL 39,67 AC-2827 CW Key 17.25 2.00 P6M10/2M 10 element Parabeam with AR-22XL 49.45 AC. 2828 Microphone Foot Switch 21.88 2.00 1,1" boom and trombone sup- AR-30 47.15 AC-2829 Headphones 40.25 2.00 port boom 36.80 AR-40 54.62 AC-2830 Lightweight Headphones 21.85 2.00 PBM14/2M 14 element Parabeam with CD-45 113.85 ir boom and 45° braces 44.85 HAM-4 166,75 KWM-380 BOOKS 5XY/2M Crossed 5 element yogi with BT-1 lelig Talkl 91,42 NTN Owners Manual 4.00 1 00 1r boom 22.77 12-X ITail Twister I 228_ 85 NTN Service Manuel 20.00 2 0()

DRAKE * SALES * SERVICE

188 BROADHURST GARDENS, RADIO SHACK LTD. LOND ON N W6 3AY

Gip Accoure No. 588 7151 Telephone 01-524 7174 Cables: Rack Shack, PilW6. Telex: 23718

RADIO COM MUNICATION June 1981 509 filICUUJAVE no D,LE 11=D LOOK!!

MASTER TX POWER AMP PREAMP

ffqii4à 144 MHz 100 WATT

414 LINEAR AMPLIFIER

MML 144/100 - S

THE NEW 144/100-S!!

FEATURES This new 144MHz solid state linear amplifier, MML144.' 100-S. is intended for use with any existing 144MHz equipment having an output power of 10 15 watts. When used in conjunction with such a drive souice this * 100 WATTS OUTPUT PO WER linear amplifier will provide an output power of 100 watts. * LINEAR ALL M ODE OPER ATION * STRAIGHT THR OUGH OPERATION WHEN TURNED OFF Several front panel mounted switches controlling the internal switching circuitry, allow the unit to be left * ULTRA-LO W NOISE RECEIVE PREA MP FRONT PANEL in circuit at all times, The linear power amplifier and the ultra low-noise receive preamplifier, which are in- SELECTABLE corporated into the unit, can both be independently switched in and out of circuit. In this way all four operational combinations are possible. • EQUIPPED WITH RF VOX AN D MANU AL OVERRIDE * LED STATUS LIGHTS FOR PO WER, TRANS MIT Ft PREA MP By means of an internal RF vox circuit the linear will automatically switch onto transmit, when 144MHz ON drive is applied to the input socket. It is possible to override this facility by the connection of an earth to pin * SUPPLIED WITH ALL CONNECTORS one of the five pin DIN power socket, located on the rear panel. This connection is compatible with all cur- rent transceiver PTT lines. The RF vox circuit is suitable for both SSB and FM modes. SPECIFICATION The inclusion of the latest state of the art power transistor (rated at I45W dissipation' guarantees highly Power output: 100 watts (within 0-5dB) typical reliable and ultra-linear performance, thus making the unit ideal for all modes of operation ISSB. FM, AM. Power input: 10 watts nominal CW and SSTVI. Power requirements: 13.8 volts @ 12 amps for 100 watts output The amplifier utilises recently developed matching techniques, which allow safe operation even when im- Overall preamp power gain: 12dB properly subjected simultaneously to 50% overdrive and a supply voltage of 15V. The PA transistor is ther- Overall preamp noise figure: Better than 1.5dB mally tracked against temperature variation and operational temperature rise. RF connectors: 50 ohm BNC Weight: 15 Kg f 3Ib 5oz) The receive preamplifier uses one of the latest dual-gate MOSFETs 135K881 in a noise-matched con Overall size - 265v 117 54mm 110,Ç 4) 21ini figuration. This technique together with careful optimisation of overall gain makes the preamplifier ideal for uso ahead of any popular 2 metre transceiver. The sensitivity of most current 2 metre transceivers is such that a preamplifier gain of 12dB is sufficient to ensure an excellent overall system noise figure. A preamplifier with gain in excess of this figure will prove unduly detrimental to the strong signal-handling EVEN BETTER VALUE AT £113+VAT performance of the transceiver. (£129.00 inc VAT) (P&P £2.75) All circuitry is constructed on high quality glass fibre printed circuit board and protection is included against reverse polarity. The unit is housed in a highly durable. extruded aluminium enclosure. TIF input and OUR ENTIRE RANGE OF PRODUCTS WILL BE EX- output sockets are located on the rear panel together with the five pin DIN power socket. Tho unit is sup plied with all necessary connectors. HIBITED AT MOST OF THE 1981 MOBILE RALLIES BY ROGER G8AYN, AND BRYON GB1WX

ALL MICROWAVE MODULES PRODUCTS ARE FULLY GUARANTEED FOR 12 MONTHS (INCLUDING PA TRANSISTORS)

BARCLAYCARD MIC R O WAVE M O D ULES HOURS: BROOKFIELD DRIVE, AINTREE, LIVERPOOL L9 7AN, ENGLAND MONDAY FRIDAY 1112: 1 Telephone: 051-523 4011 Telex: 628608 MICRO G 9 12.30, 1 5.00 WELCO ME CALLERS ARE WELCO ME, PLEASE TELEPHONE FIRST

510 RADIO COM MUNICATION June 1981 .40 VERSATOWER O HANSEN SMC-HS TELESCOPIC Et TILTOVER IN LINE POWERISWR BRIDGES OMNIDIRECTIONAL VERTICAL RADIO TOWERS P.E.P., R.M.S. 1.11-440MHz HF, VHF, UHF ANTENNAS Twelve years of continuous develop- ment has produced a range of over 50 The Hansen range covers 20 quality models HF TRAPPED VERTICAL models, all of which, being made in with top-of-the-line the FS710. This is a flat The SMCHF5V covers five bands, 10 to 80 metres. frequency response, peak envelope power and England, conform to the current S.S.S., Only 15ft 9in high, about 1din diameter and R.M.S. in-line wattmeters with many novel requiring minimum designed wind weighing 611b but with PEP handling (within the features. Most notable being the 'power in. speeds of 85mph and up to 117mph. 1.5:1 VSWR bandwidth) of 500W on 10 20m and dependent' SWR scale-no forward power 200W on 40 and 80m. It is suitable for ground moun- Before purchasalg a Tower, we strongly recom- calibration knob, just direct reading SWR. mend consulting orle of our engineers for advice ting on a good earth stake (with or without radials) regarding the most suitable combination for an F1710: or in an elevated position with resonant wire radials F571011: 1-8 60MHz. 15,150, or the SMCHF5R trapped radial kit. installation It would be incorrect to nominate a PEP 1.5kW The SMCHF5R consists of five solid rods f between specihc headload as this is dependent upon load AUTO-S WR FS7101/: 50-150MHz. 15.150W 61ft and lift) sloping downwards at 45" to the distribution, geographical location and siting. RMS LEVEL V.S.W.R: 4:1 and to 20:1 Accuracy: =7% of FSD antenna. It is the perfect answer to restricted loca- STANDARD TYPES FS710 £68 Impedance: 50-52 Ohms tions. Power; 150W PEP, weight 4lbs. Post mounting Post Mounting Connectors: S0239 SMCHF5V £35.00 SMCHF5R £26.00 Power: 240 Volts AC 50H.: [514 139,120p25 25 £252 16M20P40 40' Weight: 3.16s 11.5Kgs1 (Carriage on either or both together £1.50) 1314120P4t) 40' £345 16M2DP60 60' £584 Size overall: 8« 4 x 53 13M20P60 60' [422 16M20P80 80' £880 Size Meter: 2 x 33" Time Coast: PEP follow 4 second 13M20P80 BO' [805 16M2DP100 100' £1.061 2 METRE COLINEAR Fixed Base Fixed Base PEAK READING LEVEL RESPONSE 144MHz, 6.5dB gain and low angle of radiation £404 13M20F1325 25' £188 16M2OFB40 40' FS500 £53 FS500H 1.8 60MHz 20. 200 Er 2kW from two IA phased sections to a maximum height 13M20F1340 40' £280 16M2DF1360 60' £478 cal FS500V 50 150MHz 20 Er 200W of 3.1 metres. Three 48cm radials project from the 13M2OFB60 60' £357 15M2OFB80 80' 052 Power =7% FSD. SWR 1:1 5:1 bottom chrome-plated brass boss. A good 50ohm Size: 8x 4 x 51' 13M2OFB80 80' £739 16M20F8100100' £920 match offers better than 1.5:1 VSWR at resonance for 100W PEP plus performance over 4MHz of Socket Types Socket Types FS600 £39 PEAK READING LEVEL RESPONSE 13M2OSP25 25' £293 16M2OSP40 40' £558 operational bandwidth. Excellent weatherproof '-r FS601M 1-8 30MHz 20 fd 200W design with a S0239M connector recessed 30cm up 13M2OSP40 40' £386 16M2OSP50 60' £540 ES601MH 1.8 30MHz 200 Et 2kW FS602M 50-150MHz 20 b 200W the detachable 3.2cm OD support tube. Supplied 13M2OSP60 60' £464 16M2OSP80 80' £931 FS6COM 430 440MHz 5 Er 20W complete with mounting plate and U bolts to take £1,116 13M2OSP80 80' £847 16M2OSP100100' F_cm Power 110% F5D. SWR 1:1 3:1 llin mast. Weight 1-5kg. Base plate Base plate Size: 61 23 .41" SMCGP144W (P&P £1.50) £21.70 13M2CBP25 25' [295 16M20BP40 40' £524 13M208P40 NY £389 16M208P60 60' £S06 LEVEL RESPONSE. LARGE METER FS300 £35 FS300H 1.8MHz 20. 200 IkW, 1391120BP60 50' £464 16M20BP80 80' £902 au FS300V 50 150MHz 20, 200W FSD 70C MS COLIN EAR 13M208P8O 80' £847 16M20BP100100' £1,083 Power -±-10% SWR 1:1 3:1 =10% Wall Mounting Weil Mounting Size: 8x 4 x5,1" 432MHz. 6-8dB gain and ultra low angle of radiation 13M20W25 25' £203 16M20W40 40' £412 from three 30 phased sections to a maximum height VHF1UHF WATTMETER b BRIDGE of 1.7 metres. Three 17cm radials project from the 13M20W40 48' r296 16M20W60 60' £483 FS7 £31 FS7 145MHz Et 432MHz 5, 20. 2COW bottom chrome-plated brass boss. A good 50 ohm 13M20W60 60' [373 Mobile Type c r o Power RMS 11096. SWR 11 3:1 match offers better than 1.5:1 VSWR at resonance Mobde Typo 16M20M40 40' £1,723 Power Max: 144MHz„ 200W for 100W PEP plus performance over 10MHz of 13M20M25 25' £1,356 16M20M60 60' f1.823 432MHz 20W operational bandwidth. Excellent weatherproof Size- 61 29 , 4r. 'N' type sockets 13M20M40 40' [1.484 16M20M80 BO' £241 design with a S0239M connector recessed 23cm up 13M20M60 60' £1.576 16M2OMIDO 100' £2,316 the detachable 3.2cm OD support tube. Supplied FS711 £28 REMOTE INDICATOR TYPE complete with two extruded mast clamps and U 13M20A180 80' £1398 FS711H 1 8 3.2.1f4, 20 bolts capable of taking masts up to 2din. Weight FS711V 50-150MHz 20 El 200W 'T' Series Towers 120' sections! I -1kg. Projected area 0.034 square metres. FS711U 430 440MH: 5 Er 20W 13M20T85 85' £1,135 137.1201120 120' £1,550 Power SWR 1 I -3 1 /3':.z, SMCGP432X (P&P £1.00) £24.35 The range encompasses towers between 25 necalor 5 21 • 11" and 120ft in 10, 20 or 40ft sections mounted couwer 31 • 21 • tr on ground post, base plate, wall, fixed base or high speed trailer. FS5E £28 INDEPENDENT TWIN METER VHF/UHF DISCONES FS6E 3-5-150MHz 20, 203 Er IkW The SMCGDX1 is a vertically polarized. 3dB gain, Towers are supplied complete to brochure Power RIVIS ±10%. SWR 1:1 51 specifications. Check details of Iuffing Power Max: lkVe 3.5.30MHz 500W PEP. 50ohm, broad-band antenna. II is con gear, head unit, winches and bolts against 50W 50 150MHz structed of eight horizontal rods (each 40cm) your requirements. 1Standard items will be Size: 7.3 , 33" 'On the Air' LED radiating from a central boss, thus forming the disc, credited in full at order time). and eight rods (each 90cm) radiating from the boss •New reinforced head unit with provision FS300M £27 LEVEL RESPONSE. POWER Et SWR but sloping downward at 45° to form the cone. This for KS065 rotary bearing (E15.35 extra) is i FS301m 1-8 30MHz 20, 200W configuration produces a 1.5:1 VSWR over the now available. .FS301MH 1-8 30MHz 200. 2kW range 80 to 480MHz. ...: FS302M 50 150MHz 20. 2COW The SMCGD)(2 is a development of the GDX1 with '30ft: 10ft SECTION Power ±1O%. SWR 1:1 3:1 .±3‘.. every other disc rod extended by 72cm and every ..4.: , Size: 61.21 .41" other cone rod extended by 1.3m. This reduces the "MINITO WER" lower frequency limit to 50MHz. SWR3S £20 WIDE RANGE POWER Et SWR The SMCVHFL is a skeleton discone with three off SWR3S 3.5 150MHz 20 8 200w 8in cone and three off 24in disc elements suitable for C I O Power MaRMS s10%. SWR 1 1 3 1 Max: 3.5-30MHz listening anywhere between 65 and 520MHz. Capable of supporting e HF beam or 50W 50 150MHz AU models have an inbuilt S0239M coax connector, several VHF Ants. The head unit ac• Size: 6. 2} x 21' Antenna/syntch (in the GOX versions it is recessed into an extension coots 2- tube and provides for a of the support mast-which doubles as the coaxial rotator Operation is easy with single winch system SWR5OB £20 TWIN METER, RELATIVE POWER feed/ and are supplied with mounting hardware to SWR508 3-5 150MHz Scaled tliW ldin mast. 10M10P30 Post moult £307 ' IUD Power RMS s20%. SWR 1.1 3 1 SMCGOX1 (PE/P(1.50) £36.00 10MIOW30 Well mount ILG1013W extra) £295 Power Max: HF lkW 1:1. 300W 3:1. SMCGDX2 (PEEP (1.501 £41.70 VHF 50W 10M10BP30 Baso Plate (141) Bolts extral £325 -SMCVHFL (P&P £1.501 £14.65 Size: 6., 29 .23" 'On the Ate LED 10M1OEB30 Feed base IHD Bolts extra) £285

NB: PRICES EXCLUDE VAT AT 05%) NB: PRICES EXCLUDE VAT 115%) NB: PRICES EXCLUDE VAT (15%) DELIVERY EXTRA (estanee dependent) BUT INCLUGI POST AND PACKING CARRIAGE EXTRA AS INDICATED

SOUTH MIDLANDS COM MUNICATIONS LIMITED elZre S. M. HOUSE, OSBORNE ROAD, TOTTON, SOUTHAMPTON SO4 40N, ENGLAND elZre Tel: Totton (0703/ 867333, Telex: 477351 SMCOMM G, Telegram: "Aerial" Southampton

RADIO COM MUNICATION June 1981 511 4111 § M » 1 1 N \Ss SOUTH MIDLANDS • SMC YOUR SINGLE STOP SOURCE

On regu lar FIN, item s fCEyaesu. Ascot, SMCH5, CDE, HyGain, Channel Master, Hansen, SMC, MFJ, KIM. Mirage and Hy Mound; SMC offers free finance! (On invoices over £1001 How is it done? Simple, pay 20% split the balance equally over 6 months or pay 50% down and split the balance over a year. You pay no more than the cash price!! GA As FET RF!!!

GUARANTEE

Yaesu's own warranty does not extend outside Japan. Repairs are the respon sibility of the UK dealer selling the set. SMC's two-year guarantee is backed. as UK distributors by daily contact with the factory and many tens of thousands of pounds of spares and test equip. ment. The wisdom of avoiding hawkers T3-170L £11.85 offering sets without serial numbers, without spares, service or advice back 3 170MHz 50 ohms IkW (3 5MHz 1 1) up must be apparent. Relative power (P&P 10.8o). • í S.M.C. SERVICE Free Finance on many items. Two year guarantee on Yaesu. Free Securicor 1 delivery of major Yaesu items. Access and Barclaycard taken on the telephone. Biggest Branch, Agent and Dealer network. Ably staffed, courteous, service department. "B Services" Securicor contract at 13.50 1! Biggest stocks of amateur equipment in United FT/FP200 £335 Kingdom. Twenty two years of profes 193 10m, SSB, CW, AM. Audio filter for CW 10 aom BBB. ON, 180W PIP, C,W, FP200 AC sional communications experience. No 100W PEP 5 bands. Super mobile PSU speaker 5 Sentier Few only item too small no minimum orders.

P.S.U.s FT209R LOADS RU12040 £15 Two metre multimode portable! 4 amps cont, 6 amps surge @ 13.8 2 W output. LCD display. volts. Regulated supply (P&P £1.501 58 x 150 x 19Ornm. Repeater split, Tone burst, memories (with backupl FM; 25 RS120810 £30 and 12 ( KHz or 10KHz and 12.5KHz 8 Amps cont. 10/ 11 amps surge at 13.8 steps. SS8 1KHz and 100Hz. Tuning volts. Full foldback etc (P&P £1.501. from the microphone. A new dimension SMC 10050 3COW ,1kW ipitp C2.251 £39.85 SMC150PL 50W, 150VV ipfdp10.751 (14.95 in handbags . . and only . . . £229. SMC150N 50Wi 150W ipltp f 0.751 C24.90 SS122535 £99 • 170cms syntised handi FT708R £199)! SMC6OPL 30W, 60W !obi, f 0.501 C8.80 25A cont. 35A surge @ 13.8V. Fold SMC6ON 30W 60W lobo r 0.50i £16.50 back short circuit proof 113bP1 .2.(Xg FREE SECURIC OR DELIVERY iPRICES INCLU DE VAT @ 15% 2 YEAR IMP ORTER W ARR A NTY eze SOUTH MIDLANDS COMMUNICATIONS LIMITED S. M. HOUSE, OSBORNE ROAD, TOTTON, SOUTHAMPTON, SO4 4DN, ENGLAND Tel: Totton (0703) 867333, Telex: 477351 SMCOMM G, Telegram: "Aerial" Southampton

A G3ZUL Brian Stourbridge 1338431 5917 LEEDS CHESTERFIELD W O OD H ALL SPA rzBangorGl3KDR John 02471 55162 S.M.C. (Leeds) G Jack Edinburgh 03166512420 N S.M.C. IJack Tweedy/ LTD S.M.C. (Jack Tweedy) LTD E G13W WY Mervyn Tandragee 07621 840656 Colin Thomas, G3PSM Roger Baines. G3Y60 N Jack Tweedy. G3ZY E N OW3TMP Howarth Pontybodkin 0352871 848/324 257 Ottay Road, 102 High Street. E 150 Horncastle Road, -1- GW8EBB Peter Swansea 07921 872525 Leeds 16, Yorkshire. New Whittington, Chesterfield Woodhall Spa, Lincolnshire ,..,' GJICD Geoff Jersey 05341 26788 Leeds (05321 782326 Chesterfield 102461 453340 Woodhell Spa 10526) 52793 J, G4EOS Simon Redcar 06421 480808 9 5.30 Monday Saturday 9 5 Tuesday Saturday 9 5 Tuesday Saturday

512 RA DIO CO M MUNICATION June 1981 f / f l % \ CO M MUNICATIONS LTD I/ SMC FOR RECEIVERS—S MC FOR 2 METRE MULTI MODES

FRG7 FRG7700 * "Industry standard" receiver. * Incredible new receiver. * 0.5 30MHz. * 0.15 30MHz. * SSB ILSB/USB), CW, AM. * SSEI ILSB/USB), CW, AM, FM. * Selectivity of 2-.3kHz at -6dB. * 2.7kHz. 6kHz, 12kHz, 15kHz, @ -6dB. * Wadley loop triple conversion. * Up conversion 48MHz first IF. * 10kHz Direct dial readout. * lkHz digital plus analogue display. * Well calibrated "sharp" preselector. * No preselector, auto selected LPF's. * AM Automatic noise suppression circuit. * Advanced noise blanker fitted. * Antenna Hi to 1.6MHz, 50 ohm to 30MHz. * Antenna 500ohm to 2MHz, 50ohm to 30MHz. * 3 position RF attenuator. * 20dB pad plus continuous attenuates'. * 3 position AF filter (LP, W13P. NBPI. * Constantly variable tone control. * 110 240Vac and 12Vdc. * 110 and 240Vac and 12Vdc option. * Lights; battery economy switch. * 12 channel memory option. * Illuminated edge type "S" meter. * Signal meter calibrated in "S" and SIMPO. * Optional Battery holder £5.00. * FRG7700M £389. Memory option £83.95. T @ lee £199 INC. VA SECURICOR £309 INC. VAT @ 15% Et SECURICOR

* 144-148N1Hz inclusive Coverage. * 144 146MHz 1143.5 148.5 MHz possible). * Multimode USB•LSB-FM-AM•CW. * USEI-LSB-C W-FM (A31, Al, F31. * AC mains or 12V dc working. * 30W PIP A3j, Al and F3, I2Vdc. * Smooth Dual speed VFO. * 10W or 1W switchablo output. * Digital readout to 100Hz. Analogue IkHz. * Bandpass filter no tune design. * 22 Fix Channels (2 X 11) (2MHz). * Excellent Rs dynamic range and sensitivity. * Memory Option for split use. * Bandwidth 2.4kHz and 14kHz at 6dB. * "S"/centre zero/P output meter. * Semi break in with side tone. * Xtal cont tone burst. FM power control. * Very bright blue 100Hz digital display. * Effective noiseblanker, 20dB auenuator. * Display shows Tx and Rs freq line RIT). * Switchable AGC. * String LED display for "S" and PO. 4e Lights/readout brightness. * Digital receiver offset tuning. * Semi Break in CW with side tone. * Advanced effective noise blanker. * Clarifer on Rs or Rs Tx. * FM; 25, 121, IkHz steps. * Clarifier works on VFO, xtal Et mem. * SSS; 1,006, 100, 10Hz steps. * ALC external phono socket. * Any TX Rs split with dual VFO's. * Normal/Reverse and aux repeater shift. * -±603kHz standard repeater split. * Relay make-break-common sockets. * Four easy write-in memory channels. * Plug in board construction. * Memory scanning with slot location display. * 11.8" Dx 11.1" Wx 4.8" H (case). * Up/down tuning/scanning from mic. * Weight 20Ib (9kg). * Priority channel on any memory slot. * LED's for; MEM, Burst, NB Er Attn. * Satellite mode allows tuning on Tx. * LED's for; RPT, CLAR, VFO, MEM, On Air. * Scanning for busy or clear channels. * 25W * PEP A3j, 25W r F3. * Size (Case): 8.3" 0, 2.3" H, 6.9" W. * Highly sensitive and selective. * LED's; "On Air" Clar. Hi/ Low, FM mod. * Conservatively rated PA for low IMD. * Matching FP80 Mains PSU available.

£565 INC. VAT @ 15% VAT @ 15% Et SECURICOR £359 INC. SECURICOR

RADIO CO M MUNICATION June 1981 513 SOUTH MIDLANDS » "' SMC FOR CHOICE IN HF EQUIP MENT

FT101ZDFM * 160 10 metres including new allegations. * Variable IF bandwidth 2.4kHz down to 300Hz. * 160-10 metres including new allocations. * Audio Peak and independent notch controls. * Variable IF bandwidth 2.4kHz down to 300Hz. * AM, FSK. USB, LSB, CW, FM, (TX and RX). * 8 pole filters for razor edge selectivity. * Semi-break in, inbuilt Curtis IC Keyer. * Selectable CW fixed bandwidth CW-W and CW-N•. * Digital plus analogue frequency displays. * Semi-break in with sidetone for excellent CW. * 6146B's with negative feedback. * Digital plus analogue frequency displays. * VOX built-in and adjustables. * 61468 PA's with 6dB of negative feedback. * Instant write in memory channel. * 180W PIP and 31dB 3rd order intermod. * Tune up button (10 sec, of full power). * RF speech processor fitted-adjustable level. * Curtis Keyer- Iambic, single or straight. * VOX built-in and is adjustable from the front panel. * Switchable AGC and RF attenuator. * Wide dynamic range for big signal handling. * Optional 350 or 600Hz CW, 6kHz, AM filters. * High usable sensitivity; for those weak ones. * Clarifier (RITI switchable on TX, AX or both. * Superb noise blanker --adjustable threshold. * Audio Peak and tunable notch filter. * Attenuator; 0-10.20dB, front panel switch. * Plug in modular, computer style constructor. * AGC; slow-fast, front panel switchable. * Fully adjustable RF Speech processor. * Clarifier (RIT) switchable on TX. RX or both. * Ergonomically designed with necessary LEDs. * Low level transvertor drive output facility. * Incredible range of matching accessories. * Universal power supply 110 234V AC and 12V DC •. * Universal power supply 110 234 V AC and 12V DC. * Incredible range of matching accessories. Option. * 4 models- AM/FM; digital/analogue. •Option. VAT@ 15% VAT@ 15% £799 inc. & SECURICOR £599 inc. a SECURICOR

se e _ FT107M FT707 * 160-10 metres (including 10, 18, and 24MHz). * 80-10 metres (including 10, 18 and 24MHz bands). * USB-LSB•CVVW-FSK-A M multi-mode. * USB-LSB-C WVV-C WN-AM 1Tx and Rs operation). * Full broad band "no tune" power amplifier. * 100 W PEP. 50% power output at 3:1 VSWR. * 240W PIP. 75 per cent power output at 3:1 VSWR. * Full "broad band" no tune output stage. * 12 memory channels with clarifier on memory.• * Excellent Ra dynamic range, power transistor buffers. * Digital Memory Shift gives offset from memory.• * Ax Schottky diode ring mixer module. * Up/down scanning control from microphone.' * Local oscillator with ultra-low noise floor. * Variable IF bandwidth-16 poles of selectivity. * Variable IF bandwidth 16 crystal poles. * Bandwidths: 6kHz•, 2.4kHz .300Hz, 600Hz-3C0Hz.' * Bandwidths 6kHz•, 2.4kHz 300Hz (6C0-3501Hz• 300Hz.• * Selectable CW "fixed - widths CW-W and CW-N.• * AGC; slow-fast switchable from the front panel. * Tunable Audio Peak (AFP) and Notch filter. * VOX built-in and adjustable from the front panel. * Diode ring mixer for very high Rx dynamic range. * Semi-break in with side tone for excellent CW. * Noise blanker-front panel adjustable threshold. * Digital (100Hz) plus analogue frequency display. * AGC; slow-fast-off switchable from the front panel. * LED Level meter reads: S, PO and ALC. * Attenuator 0 20dB, plus RF gain on front panel. * Convenient concentric AF/FR gain controls. * RF speech processor fitted -front panel adjustable. * Indicators for: calibrator, fix, int!ext VFO. * Digital 1100Hz) plus analogue frequency displays. * Receiver offset tuning (RIT -clarifier) control. * Meter Reads; Vcc, lc, ALC, Compression and SWR. * Advanced noise blanker with local loop AGC. * Semi-break in with side tone, Vox built in. * 25kHz crystal calibrator feature. * Choice of built-in or separate power supply units. * Internal, xtal or external VFO control Option. 'Option AT@ 15% VAT@ 15% £609 inc. V SECURICOR £529 inc. SECURICOR

514 RA DIO CO M M UNICA TION June 1981 COM MUNICATIONS LTD \ SMC FOR CHOICE IN VHF/UHF FM EQUIPMENT FREE FINANCE + 2 YEAR GUARANTEE Available on regular priced YAESU equipment-contact SMC for details

* 144 146MHz (144 148 possible) * 12.5kHz synthesizer steps * 4 bit CPU chip for freq. control * Keyboard entry of frequencies/splits * Keyboard lockout safety feature * Digital display to hundreds of Hertz * Display auto shutdown I-1IN Control Head £120.00 inc. timer * Four easy write-in memory channels * Four Channels of * Rx priority channel (auto check) memory * Scanning of band or memory channel * Memory back up * Up/down tuning/scanning from mic. display. * Scanning for empty or occupied channels * Up/down manual * Optically coupled tuning control tuning * Easy selection of up/simplex/down * Bandscan for busy or * Manual and automatic tone burst clear channels * String LED's for 'S' and PO * Memory scanning * Seven status report LEDs features * 1+W of audio to internal/external speaker * ±-600kHz split built in * 3.3 )4. 3)" D x 6" W x 2 (2-2)" H * Any split -i- or - programmable MNIB3 Bracket for deck option £5.00 inc. * Easy change NiCad packs 720RV 10W, 2M deck £133.00 inc. * BNC antenna connector 720RVH 25W, 2M deck £143.00 inc. * "On Air" and "Channel Busy" LEDs * 144 -14.6MHz (144-148MHz possible) * Built in condenser microphone * 12¡kHz sythesizer steps * 200mVV AF to internal/external speaker * -±-600kHz repeater offset * External speaker/ mic available * 0.3faV for 20dB quieting * 2-5/0-2 W of RF output * Rx 0-5A. Tx RV 3- 5A, RVH 6- 5A * Rx; 35mA squelch, 150mA full vol. * 10.7MHz & 455kHz double conversion * Tx; 250mA low, 800mA high * 5.8 16.51" D x 6" W x 2(2.2)" D * 0.3uV for 20dB quieting 720RU 10W, 70cm deck £I56.00 inc. * Double conversion 10.7MHz and 455kHz * 430 434MHz * Two-tone encoder built in * 25kHz synthesizer steps * 1-7 12-21" D x 2.5 12.71" Wx 6.7 17.2)" H * 1.6MHz repeater shift * Clw NiCads, helical and case * 0.5/V for 20dB quieting YM24A External speaker Mic £16.85 inc. * Rx 0-5A, Tx 4-5A PA2 12V DC adaptor £13.40 inc. * 16-9MHz + 455kHz double conversion M MB 10 Mobile Bracket £5.75 inc. * 5- 8 (6. 5)" D x 6" W x 2 (2.21" D NC9C Mini Charger £7.65 inc. E72S Extension cable 200cm £23.00 inc. NC 'IA Mains Charger £19.15 inc. E721 Extension cable 400cm £28.00 inc. NC 2/3 Mains quick charger/eliminator £39.50 inc. S72 Switching box £56.00 inc. NC 3 Charger/eliminator/12V adaptor . £42.55 inc. * Permits control head with two decks NBP9 NiCad pack (spare/ £16.85 inc. * Single button change of band FLC2 Heavy Duty leather case £20.70 inc. * Auto change of synthesizer steps er repeater split. W MT207R Workshop manual £4.00 FT720RV, 101N, 2 metre. FT207R, 23-W, 2 metre.

£253 inc VAT @ 15% Et SECURICOR £175 inc VAT @ 15% Et SECURICOR

eze SOUTH MIDLANDS COMMUNICATIONS LIMITED S. M. HOUSE, OSBORNE ROAD, TOTTON, SOUTHAMPTON, SO4 4DN, ENGLAND Tel: Totton (0703) 867333, Telex: 477351 SMCOMM G, Telegram: "Aerial - Southampton

A G3ZUL Brian Stourbridge (0384.3) 5917 LEEDS CHESTERFIELD WOODHALL SPA G13KDR John Bangor (02471 55162 G s.m.C. (Leeds) S.M.C. (Jack Tweedy) LTD * S.M.C. (Jack Tweedy/ LTD GM8GEC Jack Edinburgh (031665) 2420 N N E G131/iVi/Y Mervyn Tandragee (07621 840656 Colin Thomas. G3PS M Roger Baines. G3YBO Jack Tweedy, G3ZY E N G W3TMP Howarth Pontybodkin (035287) 846/324 257 Otley Rond, 102 High Street. E Horneastle Road. G W8EBB Peter Swansea (0792) 872525 Leeds 16. Yorkshire New Whittington, chesterfield. W Woodhall Spa, Lincolnshire. GJICD Geoff Jersey (05341 26788 Leeds (0532) 782126 Chesterfield 10246) 453340 * Woodhall Spa (0626) 52793 G4ECIS Simon Recker (06421 480808 9 6.30 Monday Saturday 9 6 Tuesday Saturday 9 5 Tuesday Saturday

RADIO COM MUNICATION June 1981 515 COUNCIL RADIO SOCIETY OF GREAT BRITAIN President (Limited by guarantee) B. O'Brien. G2AMV Registered office: 35 Doughty Street, London WC1N 2AE Executive vice-President J. Anthony, BSc, MIETE. G3KOF Telephone 01.8,3/ 8688 Telex 25280 IRSGBHO G) Honorary treasurer Founded 1913. Incorporated 1926. Me mber society, International Amateur Radio Union P. F. D. Cornish, FCA, G3COR Ordinary me mbers P ATR O N: H R H The Prince Philip, Duke of Edinburgh, K G E. J. Allavvay, MB, ChB, MRCS, LRCP, G3FKM J. Bazley, G3HCT The national society representing all UK radio amateurs R. Bellerby, MA, BSc, FBIS, G3ZYE D. S. Evans, PhD, BSc, F1M, G3RPE Me mbership is open to all those with an active interest in radio experimentation and com munica- K. A. M. Fisher, TEngICE11, M1PRE. G3WSN tion as a hobby. Applications for membership should be made to the general manager, from G. R. Jessop, CEng, MIERE, G6JP whom full details of Society services may also be obtained. D. M. Pratt, BTech, CEng, MIEE, MIERE. G3KEP G. M. C. Stone, CEng, F1EE, FIERE, G3F2L GENER AL M A N AGER AN D SECRETARY EDITOR Zonal me mbers D. A. Evans, G3OUF A. W. Hutchinson Zone A. J. Heathershavv, G4CHH (Mrsl Zone B. J. Anthony, G3KOF AN NU AL SUBSCRIPTION RATES Zone C. (Post vacant) Zone D. L. Havvkyard, G5HD UK corporate: £12.50, including VAT Overseas: £12.50 Zone E. R. G. Barrett, GW8HEZ Associates under 18: £5 Family member: £5 Zone F. (Post vacant) Students aged 18 to 25: (7.50 (Student applications should give the member's age at last renewal Zone G. G. L Knight, GM8FFX date and include evidence of student status) Associated societies: £12.50 (including Rad Conn: £7.50 (excluding Rad Coml.

REGIO N AL REPRESENTATIVES Region 1 W. M. Furness, G3SM M RSGB SUNDAY NEWS BROADCASTS Region 2— D. Smith, G4DAX These broadcasts are made every Sunday morning on hf and vhf, giving almost complete coverage of Region 3— H. S. Pinchin, G3VPE the British Isles. All stations broadcasting these news bulletins use the callsign GB2RS, and infor. Region 4-- M. Shardlow, G3SZJ mation regarding them is given in the table below. Region 5—R. E. G. Kendall, G8BNE The purpose of these news broadcasts is to provide an outlet for amateur radio news items which, Region 6—F. S. G. Rose, G2ORT by virtue of their topicality or urgency, cannot wait for the next issue of Radio Communication. The Region 7-0. A. G. Pedder. G3LFX bulletins are compiled on Wednesday mornings, and items for inclusion should reach RSGB HO by let- Region 8— D. N. T. Williams, G3MDO ter (marked "GB2RS news") or telephone before 10am on Wednesday. No guarantee can be given of Region 9—H. W. Leonard, G4UZ inclusion, in whole or in part, of any item submitted arid, once broadcast, items are not usuallY Region 10— P. A. Jones, GW4HAT repeated. Region 11—P. H. Hudson, GW31E0 INTENDED RECEPTION NOR MAL RESERVE LOCAL START Region 12— F. Hall, GM8BZX AREA READER READER TIME Region 13—A. B. Givens, GM3YOR Region 14—C. W. Tran, GM3WOJ Frequency: 3.640MHz. Mode: ssb Region 15 —1. Kyle, GI8AYZ NE Scotland GM3HGA GM3VEY 1130 Region 16— M. S. Appleby. G3ZNU Region 17 — H. G. Cunningham. G8FG Frequency: 3.650MHz. Mode: ssb SE England Region 18—W. Ricalton, G4ADD G2MI G4ARZ 0900 Region 19— R. J. Broadbent. G3AAJ Midlands G2CVV GBOZ 0930 Region 20— B. L. Goddard, G4FRG SW England) Wales G8ML G3,JFH 1000 Northern Ireland GI3GAL GI3SXG 1030 NE England G5V0 G3MCE 1100 E Scotland GM4CUZ GM4FLP 1430

Frequency: 3.660MHz. Mode: ssb Central Scotland GM3TC W GM3ULP 1130 HO N OR ARY OFFICERS Audio tape and slide library co-ordinator Frequency: 7.0475MHz. Mode: a.m. D. Simmoncls, G3JKB UK (from Northern Ireland) GI3GGY GI2DHB 0900 UK (from N Midlands) G3LEC) G2CVV 1100 Awards managers hf — P. Miles, G3KDB Frequency: 144•250MHz. Mode: ssb horizontal polarization) vhf —Jack Hum, G5UM SW from the Midlands G3BA G3KOF 0930 Emergency com munications manager NE from S Devon G3CHN G3PBV 1000 Post vacant NW from Manchester G3SMT G4IAL 1000 NNW from Cleveland G4JJB G8FTZ 1000 HF manager W from Carlisle G4LAA (Vacancy) 1030 E. J. Allaway, G3FKM SE from Lincoln G8OFQ G3NRO Intruder Watch organizer SW from London G3FZL.iG3VAG G3IIR 10%( S. Cook, G5XB S from Aberdeen GM8GHViGM8MBP 1030 W from Bristol G4CJZ G3ZWY 1100 Observation Service organizer W from Bangor, Co Down GI3TLT GI3SXG 1130 D. M Pratt, G3KEP Microwave manager Frequency: 145.525MHz. (S21) Mode: fm (vertical polarization) D. S. Evans, G3RPE Cornwall G2ABC G3NPB ,G3VG0 0930 Hampshire, north G8CKN G3PZN 0930 Slow morse practice transmissions organizer Suffolk G3ZNU G4FSG 0930 M. A C. MacBrayne, G3KGU Leeds G3SPX G8XGN 0930 Telecom munications liaison officer Co Down 013WEM Gl4DOR 0930 R. F. Stevens, MBE, G28VN Edinburgh GM4EHO GM4JFS 0930 E Cornwall/S Devon G3ZYY G4G WJ/G4KYY 1000 Trophies manager Londonderry GI2DHB GI4AHD 1000H P. A. Miles, G3KOB London G3FZ UG3VAG G31111 1000 VHF manager Birmingham G3P WJ G3BA 1000 K. A. M. Fisher, G3WSN Lincolnshire G8OFQ G3NRO 1000 Tyneside G4FUT Video tape and film library co-ordinator G3WNR 1000 Glasgow GM4HCO J. Anthony, G3KOF GM4CXM.+GM3VTB 1000 Elgin GM4ILS (Vacancy) 1000 Correspondence to RAs and honorary officers should be Carlisle G4LAA G80ALI 1100 Southampton addressed directly to them (OT/IR), not to RSGB HQ. G8LVC G8ADM 1030 E Sussex coast G8SC G3ZFE 1030 Bristol G4CJZ G3ZWY, G8NNU 1030 Manchester G3LEC1 G3JWK 1030 RSGB QSL BURE AU Brighton and coast G3ZYE. G8GEZ G4JGJ / AM 1100 OSL cards for distribution should be sent to: Jersey GJ8KNV GJ4ICD 1100H Mr E. G. Allen. G3DRN. QSL Bureau manager, Gwynedd G W4KEV G W8TTM 1100 30 Bodnant Gardens, London SW20 OUD H = horizontal polarization

516 RADIO CO M MUNICA TION June 1981 Thanet Radio Club OBITUARY Mr G. Abrahams, G4KE.1, 5 Minnis Road. 'Wellington, Kent. would be pleased to hear from anyone who would be interested in re-forming the Thanet Radio Club. Peter Balestrini, G3BPT Stolen equipment From a member's shack and his car, parked outside, on 20 April: Sugiyama F850 multiband transceiver, serial number E00125; Zycomm Immediate Z5800 144MHz handheld transceiver, serial number 08550494, less past-President charger; FDK Multi-U I 1 432M Hz mobile transceiver, serial number 86087. Any information to C. 1). Tabor, G3UGR, Banksia. Queen Camel, Yeovil. Somerset, or to the police. The RSGB records with deep regret the death on 30 April 1981 of Peter Balestrini, G3BPT, who was President of the Society last year. At the time of his death he was attending the IARU Region 1 Conference In RAE course Brighton in his capacity as RSGB emergency communications An RAE course is being run at the Bridgnorth & South Shropshire College manager, where he chaired a working party, on emergency of Further Education on Wednesday evenings from 6.30 to 8.I5pm. If communications in Region 1. there is sufficient demand, a morse course on another evening could be Peter joined the Society in 1950, and took up his first com mittee appointment in 1964 when he became a member of the RAEN (now offered. Raynet) Com mittee, of which he remained a stalwart member until his Enquiries to Mr A. T. Smith. head of engineering, at the college. death. He became a member of Council in 1974 and subsequently served on several com mittees, and was chairmen of the Raynet Committee for several years. In 1977 he was appointed the Society's Mid -Lanark ARS open day first emergency communications manager, and his contribution to the The Mid-Lanark ARS will hold an open day on Sunday 21 June at work of the Society was honoured by his election as President in 1980. Wrangholm Hall. Jerviston Street, New Stevenson. Motherwell. A pro- His death deprives the Society and amateur radio of an indefatigable worker. particularly in Raynet. His memory will long be honoured by all gramme of lectures, a bring and buy salc, junk and trade stands are being who knew him. arranged. Refreshments available all day. Ample car parking. Talk-in on 144.55MHz. (ADCS operational. Doors open 1pm.

REGION 2 ORM Sunday 21 June 1981 (During the Denby Dale Mobile Rally) Shelley High School, Near Huddersfield

Easy access from junctions 38 and 39 on Ml, and junction 23 on M62. One mile from Emley Moor tv mast

Talk in: GB4CDD on S22. GB8CDD on SUB

Rally from 1130 11030 for RAIBC) to 1700 1982 RSGB Amateur Radio Call Book OR M starts at 1430 The lists of RSGB affiliated societies and clubs and RSGB groups for this RSGB Council members and headquarters staff will be present. edition will he compiled from information obtained front the RSGB HQ computer at the end of July. RSGB bookstall Thirty trade stands Secretaries of these clubs etc should ensure that the particulars and ad- BYLARA meeting Bring and buy sale RAIBC stand Children's film show dress for correspondence of their respective clubs are correctly recorded on Fashion lingerie RSG13 HQ records well before that date.

regions are invited to vote for one of the candidates in Watford P. Marcham, G3YXZ ELECTION OF RSGB their respective region. Region 3 comprises Hereford N Devon H. G. Hughes, G4CG REGIONAL fer Worcester. Shropshire. Staffordshire, Warwickshire Basingstoke P. J. Steffy. G3CBU and West Midlands. Region 8 comprises Kent, East Cheshunt J. Sleight, G30JI REPRESENTATIVES Sussex and West Sussex. Pontefract P. N. Butterfield, G4AA0 Votes should be recorded on the ballot form printed Liverpool B. Donn, G3XSN The following nominations for RSGB regional on the reverse of the label carrier used for mailing this Peterborough L. Critchley, G3EEL representatives to serve for the period July 1981—June issue of Rad Com, and should be sent to: The General Harrogate Et 1984 have been received: Manager, RSGB, 35 Doughty Street, London WC1N Wetherby K. M. Clearly, G4ATZ Region 1—W. R. Parkinson, G3FNM 2AE, to arrive not later than Friday 26 June 1981. Mark Basildon R. W. Howe, G3PLB Region 2—D. S. Smith, G4DAX the envelope (Regional election). Lisburn G. Moore, GIBYTH . S. Pinchin, G3VPE In those regions for which no nomination has been Lothians J. McVicar, GM8GEC Region 3 W. Ross, G8M WR received, RRs will be appointed by Council, which will Horsham, Crawley Region 4- (M. Shardlovv, G3SZ..1, to continue in be pleased to consider any recommendations from Et Mid-Sussex J. Brooker, G3JMB office; appointment held for 12 months members in those regions so that suitable appoint- Harwell C. Sharpe, G2HIF or less) ments can be made. Any such recommendations Bangor INI) H. Irvine, GI3TLT Region 5- (No nomffiation received) should be received by 26 June. Weymouth Er Region 6 - F. S. G. Rose, G2DRT Dorchester G. M. Taylor, G8HVY Region 7- (No nomination received) Scarborough J. R. de L. Simpson, G3CAA .{A. K. Baker. G4GNX Coventry W. F. M-Hahn, G3U0l. Region 8 - K. A. Crouch, G8KEN ELECTION OF RSGB AREA SE Somerset G. Symons. G3DSS G. D. Edy, G4AXD REPRESENTATIVES Blackburn N. Jenkin, G4CGT Region 9—W. J. Colclough, G3XC Derby J. Shardlow (Mrs), G4EYM Region 10- (No correct nomination received) The following nominations for RSGB area represen- Belfast C. S. Robinson, GI4JOX Region 11— B. H. Green, GW8AAA tatives to serve for the period July 1981 — June 1984 E Cornwell A. E. Warne, G3YJX Region 12— F. Hall, GM8BZX have been received. The list also includes area Scunthorpe J. A. Sheardown, G8TIY Region 13- No nomination received) representatives who have held office for 12 months or E Antrim P. McMichael, GI4LKA Region 14- No nomination received) less and who have indicated that they wish to continue Exeter A. C. Courtney, G8X1P Region 15-J. T. Barnes, GI3USS in office for the above period. Wirral J. Fogg. G8UZZ Region 16- No nomination received) Londonderry J. A. Porter, GI3GGY Region 17— H. G. Cunningham. 68FG Lincoln B. Bennett, G3EAM SE Kent K. A. Crouch, G8KEN Region 18— W. A. Ricalton, G4ADD Chelmsford L. V. G. Turner, G4CUT Bradford & Halifax M. Topham, G8NUC Region 19— R, J. C. Broadbent, G3AAJ Cheltenham R. W. Marshall, G4ERP N Ulster T Hamilton GI4HVI Region 20— B. L. Goddard. G4FRG Jersey A. D. Morrissey, GJ3YLI Hereford S. H. Jesson, G4CNY Ballots will therefore be necessary for Regions 3 Guernsey J. E. Martin, GU3YIZ No area having received more than one nomination, and 8, and corporate members resident in those W Cornwall B. H. Body. G8JML no elections for area representatives will be necessary.

RADIO CO M MUNICATION June 1981 517 The RX80 Mk2

A 3.0-4.0MHz ssb/cw receiver and tunable i.f. for a complete hf receiver

(Part 5)

by A. L. BAILEY, G3WPO*

THE PS80 MAINS POWER SUPPLY Fig 36. The PS80 pcb

To complete the RX80 hf receiver proper, the mains power supply module to be described may be mounted in the space provided at the rear right- hand side of the cabinet. The psu is built on a single-sided pcb, with one external capacitor, and uses a low-profile pcb mounting transformer with two 15V windings which are paralleled in use. The circuit (Fig 35) uses a simple series regulator (TRI) with its base cur- rent regulated by TR2, which in turn derives its reference voltage from an I IV zener diode, D5. The output voltage is a nominal 11.6V. A three ter- minal regulator was avoided in this design, due to the rf noise inherent in these devices, and simple precautions have been taken to reduce voltage spikes at the output. No detailed constructional notes are given, due to the simplicity of the circuit, but as mains voltages arc involved the following points should be observed: (1) The pcb must be earthed to the connection pin provided, both to the mains input socket earth tag and to the chassis of the receiver. Also the area on the underside of the pcb carrying the mains transformer should be varnished or a suitable piece of insulating material fixed to it, to avoid ac- cidentally touching the pins if the pcb is removed or anything gets under the pcb when mounted. The two leads carrying 240V ac input to the pcb should be connected directly to the pcb through the holes, with the lead in- sulation carried right to the pcb upper surface. Finally an insulating shroud around the transformer itself will remove any mains hazard from The PS80 mains psu the upper side of the pcb. Suitable insulation of the chassis end of the mains socket, if not already provided, is also advised.

FS1 500mA +11-6v o R1 1 TIP31ATR1 5600

® 05 11V

Fig 35. Circuit diagram of the P580 C7 - C8- .17 V —e —2200e R2 10p" -4700; TRI100 fe y3 BC239 15V Two, I18W2R3 JI o '9 Alberta Walk, Worthing, West Sussex, BN13 2SG

518 RADIO COMMUNICATION June 1981 Matera' 1/16.thcn smgle•slcIed glass-fibre printed circuit board Size-99 x 89mm PS80 components list R1 560f2 112 100f) 113 180f2

C1,2,3,4 0-01uF disc ceramic C5 2,200uF 25V electrolytic (axial leads) C6 10(F 16V electrolytic (radial leads) C7 10uF 16V electrolytic (radial leads) C8 4,700µF 16V electrolytic (axial leads)

TR1 TIP31A TFt2 BC239, BC109

01 -D4 1A 50V bridge rectifier type WO-005 D5 BZY88 400m W 11V zener diode

FS1 500mA mounted in pcb mounting fuse clips

Ti 0-15, 0-15V, 6VA pcb mounting transformer type P0615 Resistors are 0.25W 5 per cent carbon film. C5 must not be larger than 30rnm dia by 43rnm long to fit pcb. C8 is mounted externally to pcb. A drilled screened pcb is available from Ambit International together with the other components, either separately or as a kit.

Four additional mounting holes are required in the chassis cen- tre panel for the pcb as shown in Fig 39. The pcb is mounted on 6BA bolts with two 6BA half nuts as spacers between pcb and chassis. C8 should be mounted at the rear of the receiver case as close to the psu as possible. Holes shown • are 0.85rnrn dia 4 holes 'A' 3mrn cha 10 holes '13 . 1mm dla 19holes 'C' 1.2mm dia

Fig 37. PS80 pcb drilling details Dimensions are in millimetres Rear (toe view) 20 • A A (2) Cut off all pins close to the pco track after soldering. 41> C (3) Use a fuse with the rating recommended (500mA). (4) TRI must be provided with a heatsink. 29 (5) If an 11V zener is not to hand, use two 5.6V zeners in .eries, or 10V plus two 1N4148 diodes in series. Output voltage from the psu should not exceed 11.8V.

çt 81 0

mains socket Chass.s.4— 'earth terminal

o \111/ 240Vac L 0 C. A A ‘"

o

Heat sink N 0 0 0. 0 o

4 holes 'A'...3mm dia

•-f" P3 j-• Fig 39. Additional holes for the psu pcb mounting

R1 R2

- o o

b. • •c e• TR2 1. -28 15 I 28

.q FS1 . 3mam 5 I 500mA 03 I

—1 7.5 —• C5 25 C3 02 C4 Bend at dotted lines to form U. shape o Material ....14 to 18 swg aluminium sheet e iddicates CO,neCting 1.)0 Dimensions are in millimetres

Fig 38. PS80 component layout Fig 40. Heatsink for TR1

RADIO COMMUNICATION June 1981 519 Centre line f. 30

30

40

1

130 IC O 130

130 130

:Both cut-outs are Identical

310 BOTTOM FRONT 1 u TOP FRONT Dimensions are in millimetres

Fig 41. Ventilation cut-outs for covers

Fig 41 gives the dimensions of the additional cut-outs. the one in the top Ventilation of the case cover having been extended right across the top to provide the speaker hole In order to minimize receiver drift due to heating (especially if the as well. All of these should be covered with a suitable open mesh grill to stabilizer is not fitted) ventilation cut-outs are required in the case top and finish off. bottom covers. At the time of preparing the drawings for the case, the psu had not been fitted and hence these cut-outs were not shown. If the case Additional receiver facilities described in Part 3 (Rad Corn March 1981) has already been made and The articles in this series so far have described various modules with which these additional cut-outs pose any problems, the psu may be used in a an hf receiver can be constructed. Further articles to follow will describe a separate external enclosure, and this will of course avoid any warm-up 144MHz converter and fm LI.., and component changes to enable the main problems. RX80 tunable i.f. module to cover the 2 3MHz band.

TO BE CONTINUED

CORRECTIONS TO PART 2-CV80 HF CONVERTER

Unfortunately while drafting this part of the article a number of omis- there is little point in changing the pcb connections to correct the sions and errors crept in for which the author apologizes. These are preset earth connections. New constructors should use the pcb corrected here. layout published here (Fig 13 amended), and all kits supplied from (A)The wiring connections shown in Fig 13 were not given reference mid-April will llave had the correct pcb. letters, and the link on the pcb between points A and B was shown (D)C19 was omitted from the components list; it is 10pF ceramic. incorrectly. If wired as originally shown, TR7 is probably now (E) In the third note to the components list, the crystals are HC18-U, blown. Also, TR6 and TR7 were omitted from Fig 13. not HC25-U as stated. (B) Alignment note 6 should read: (F) Referring to Fig 10 (circuit diagram) TR6 is shown incorrectly— the 6. Connect an antenna, and 12V to point F. wiper of RV3 should go to TR6 base, and the end shown con- (C)The presets VR1,2.4 and 5 are connected on the original pcb nected to TR6 base should go to the RX80 agc line. The original layout in a different manner to the circuit diagram and results in pcb layout was correct. the tuning diodes having a smaller available capacitance swing. A further alignment tip is that C21 should be adjusted to give a sud- Provided the converter as built is working and aligns correctly den increase in the noise level, indicating that the oscillator has started.

Fig 11 (amended,. Corrected Cv80 printed circuit board

520 RADIO COMMUNICATION June 1981 To RX80 Link on pc b RV5 wiper Output to RX80 +12V +12v Tunable I f (converter) (tuning)

TUNE OB C2A

• TR. — G - • • C15 u«- • • •

• T3 To antenna Fig 13 (amended). o • • Corrected CV80 AGC • component u •C9 • • layout and wiring C23 TR6

Sloping side-.- AGC in • • • To RX80 IC2, pin 2 • indicates connection pin 2SK55 viewed from top

Thandar SC110 oscilloscope The Thandar SC) 10 is a portable oscilloscope having dimensions of 10 by 5.8 by 2in, and weighing under 21b. It has a 10MHz bandwidth, and sen- sitivity down to 10mV per division. The SC) I' uses a 2in diagonal crt tak- ing very low power which, combined with circuitry which automatically shuts down unwanted sections of the instrument, enables it to operate for The Thandar TG100 function generator long periods on low-cost disposable batteries of between 4V and 10V dc. The small size and weight of the instrument make it truly portable yet hav- case, the TG100 combines ruggedness with portability and light weight. ing the performance of a standard bench oscilloscope. Designed and manufactured in England, the TG100 comes complete with mains lead and a one-year warranty, at a cost of £79 plus VAT. Further details from Sinclair Electronics Ltd, London Road, Si Ives, Hun- tingdon, Cambs PE17 4HJ. Tel (0480) 64646.

Thandar TF040 led bench frequency meter The TI-040 is a battery operated eight-digit led frequency meter with totalize facility, which measures frequencies from 10Hz to 40MHz with a sensitivity of better than 40mV rms. The large 0.5in display reads out directly in kilohertz and also has indicators for gate, overflow and low bat- tery, with automatic positioning of decimal point. Typical battery life is 80h from six alkaline "C" cells, and the meter can also be operated from an optional ac adaptor. Including batteries the TF040 costs £110 plus VAT. Further details from Sinclair Electronics Ltd., London Road, St Ives, Huntingdon, Cambs PE17 4HJ. Tel (0480) 64646.

The Thandar SC110 oscilloscope

The SC110, from Sinclair Electronics Ltd, was the only British product to win a gold medal at the 1980 BRNO Trade Fair in Czechoslovakia. Price £139 + VAT . Further details from Sinclair Electronics Ltd, London Road, St Ives, Huntingdon, Cambs PEI7 4HJ.

Thandar TG100 function generator The latest low-cost professional bench instrument trom Thandar is the TGI00, mains operated, I Hz-100kHz function generator. It has selectable waveforms of sine, square, triangle and dc from a variable amplitude 600Q The Thandar TF040 Icd frequency meter output. A ttl output is also provided. Housed in the distinctive Thandar

RADIO COMMUNICATION June 1981 521 Drake TR7 hf transceiver

by P. A. BARRON, BSc, G3VVTM, and P. J. HART, BSc, G3SJX*

T HIS review has been compiled from two independent assessments of I the Drake TR7 hf transceiver. The earlier equipment was obtained in February 1979, serial No 2088, and the later in March 1980, serial No 4709. Both transceivers incorporated the digital readout/general coverage receiver option (DR7) and were fitted with additional filters for cw, a.m. and rtty. The TR7 is an hf transceiver of the "new generation" employing the latest techniques. Broadband circuitry and a high first if. are used, which eliminate the need for the customary preselector and pa tuning controls, and allow the possibility of full general coverage operation. It is intended for 12V battery operation, and standard features include passband tuning, calibrator, vox, irt and directional wattmeter. Optional features include noise blanker, digital readout combined with general coverage on receive, up to three additional selectivity settings and vif reception. A range of matching accessories is available, including mains psu, remote vfo, anten- na matching unit, external speaker and microphone.

Description The transceiver is sturdily constructed and well screened. A compact layout has been achieved, with most of the circuitry constructed on plug-in boards. The power amplifier is mounted on a heavy cast hcatsink as a separate assembly inside the main chassis. Board extenders are available at extra cost to aid in Sind servicing of the plug-in boards. The transceiver measures 35cm (w) by 12cm (h) by 32cm (d) and weighs 7.75kg. The PS7 mains power supply is similar in size but nearly twice as heavy. The front panel controls are well laid out and easy to use. Full vox and cw break-in controls are adjustable from the front panel, and many func- tions are push-button controlled. The analogue dial, fitted as standard, can be read to I kHz, and the digital readout, available as DR7 option, provides readout to 100Hz. The tuning rate is adequately slow at 25kHz per revolution of the 40mm diameter knob, but not as slow as some other transceivers. Both reviewers would have preferred a larger diameter tuning knob. A standard four-pin microphone connector is used, although the pin connections differ from those used by most Japanese manufacturers. Both crystal and dynamic microphones may be used, and there appears to be ample audio gain available. A number of external facilities are available through connectors mounted on the rear panel. Provision is made for external receiver, in- dependent receiver antenna, low level audio output, linear amplifier con- trol and ale, remote vfo, fan, a comprehensive accessory connector etc. The digital frequency display may be used as an external frequency counter operating at frequencies up to 150MHz with 100Hz resolution. No provision for low power output is provided, which makes this transceiver difficult to use with transverters. A block diagram of the TR7 is shown in Fig I. Incoming signals pass through band-switched low-pass and high-pass filters and are then up- converted to an if, of 48.05MHz using a packaged high-level double- balanced mixer. No rf amplifier is used. A low-noise, wide-dynamic range amplifier is used at 48.05MHz to precede the 10kHz-wide roofing filter. The main selectivity is achieved at the second if. of 5.645kHz. The second i.f. amplifiers and audio adopt conventional practice.

•42 Gravel Hill, Addington, Croydon CRO

522 RADIO COMMUNICATION June 1981 On transmit, ssb generated at 5,645kHz is converted first to 48.05MHz Audio and then to the final frequency via the same mixers and filters as are used Signal T 157 power generator on receive. These mixers, being double-balanced diode mixers, are meter bilateral and will operate with the signal flowin either direction. The wide- band power amplifier is fully solid-state. Both alc and vswr shut down are (a) provided by a PIN diode attenuator in the 5,645kHz LI'. transmit path. When on cw a separate cw oscillator is enabled to give the transmit signal Signal generator and sidetone for receive. A Local oscillator drive for the second mixer and bfo injection are derived from two crystal oscillators mixed with the output of a third voltage- Audio Hybrid Variable TR7 power combiner - attenuator controlled crystal oscillator (vcxo) adjusted by the passband tuning con- meter trol. This results in a change in frequency of both the second mixer oscillator drive and bro and allows the second i.f. to be positioned (b) anywhere within a ±3kHz range with respect to the crystal filter passband while the receiver remains tuned to the incoming signal. The local oscillator drive for the first mixer is synthesizer controlled. The main tuning dial controls the frequency of a permeability-tuned oscillator (pto) in the frequency range 5.05-5.55MHz. The synthesizer Spectrum reference frequency is derived from a 40MHz crystal oscillator divided analyzer down to 500kHz. A veo operating in the frequency range 48.05-78-05MHz provides the first mixer local oscillator drive and is Two-tone Power a f T R 7 attenuator phase locked in 500kHz bands to the pto. The division ratio in the signal Oscillator feed to the phase detector determines which 500kHz band is selected. The division ratio lies in the range 665 and is determined by the band selector (c) Thermocouple switches. power meter The PS7 mains power supply gives 13.6V at 25A stabilized with current limit and overvoltage protection. Fig 2. Test arrangements used for this review

the source emf. Unless stated otherwise, all measurements were made us- Measurement technique ing the 2.3kHzAvide ssb i.f. filter selected, and the audio gain set to give Both transceivers were reviewed independently using laboratory-grade test 100mW af output. equipment. The test arrangements adopted are shown in Fig 2. The single generator arrangement (a) was used to evaluate sensitivity-based measurements and spurious responses. The two-generator arrangement (b) Receiver measurements was used to evaluate signal handling, ie blocking, crossmodulation, inter- Sensitivity modulation and reciprocal mixing. For intermodulation measurements it Sensitivity measurements were made at a signal plus noise-to-noise ratio is important to ensure that no intermodulation products arc generated (s + n)/n of 10dB. For a.m. measurements the generator was modulated to within the generators when the two are coupled together. For this reason it a depth of 30 per cent with a IkHz tone and the 6kHz wide a.m, i.f. filter is essential to use a hybrid combiner which provides isolation between the selected. The results obtained for the later transceiver are shown in Table I two input ports rather than a resistive combiner. The loss of the hybrid and indicate a noise floor on ssb of about — 13IdBm in a 2.3kHz band- combiner and attenuator combination must be known in order to deter- width. This figure is well within the published specification. The earlier mine the signal input to the TR7. transceiver is about 5 to 6dB less sensitive. Modifications made to the later In all cases in this review, signal input voltages arc quoted in pd across model TR7s account for this difference. the antenna terminal. Signal generators are often calibrated in terms of source emf. Where a generator of 50S2 source impedance is connected to a Spurious responses receiver of 50fl input impedance, the pd across the antenna terminal is half The 48.05MHz i.f. rejection and the image rejection at + 96- I MHz arc both shown in Table I. These are the results obtained with the later transceiver. Figures obtained for i.f. rejection with the earlier transceiver are similar, but figures for image rejection are about 20dB worse. This dif- ference is due to the improved screening adopted in the later transceiver. Improved screening is the major difference between the two transceivers. Many of the internally-generated spurious signals found on the earlier transceiver arc absent on the later transceiver. Carefully tuning the later transceiver over the complete range 1.5-30MHz with the antenna socket terminated in a 5012 load. 15 spurious signals greater than Si were logged. Two of these were in amateur bands, 7.055MHz (S2) and 14.121MHz (S3). The strongest spurious signals were found on 5-645MHz (S8) and 5.339MHz (S6). A large number of weak "birdies" was audible in the range I -5-2-5MHz and 4.5-6MHz. Operating the TR7 with the case or any screening covers removed considerably worsens the pick-up of spurious signals. It was found that operating the earlier transceiver with the RV7 external vfo eliminated many of the spurious signals. This has not been checked on the later transceiver.

Table 1. Receiver measurements

Frequency Sensitivity ssb Sensitivity a.m. Image rejection IF. rejection 1.8MHz 0.2oV 1. 5pV 108d8 78c1B 3.5MHz 0.18µV 1 4pV 109d8 81c1B 7MHz 0.18oV 1.41.4V 108dB 86d8 10MHz 0.24N 1.5 0 107dB 86dB 14MHz 0• 11V 1 • 4pV 107dB 87dB 18Mhz 0.2oV 1 • 5pV 107d8 92dB I 21MHz 0.2pV 1.514V 107dB 24M Hz 0-244V 1 .61.4V 104dB 86d8 28M Hz 0.230/ 1 131,4V 103dB 86d8 Top view of the TR7 with cover removed 30M Hz 0.23oV 1 • iipV 104dB 86dB

RADIO CO M MUNICA TION June 1981 523 Table 2. S-meter calibration

S-reading S5 S6 S8 S9 S9+20 S9+40 S9+60 S9+80 Input signal 3.25pV 9pV 15pV 30,V 300pV 3.5mV 32.5rnV 250mV Earlier Relative receiver increase to 9dB 4.5dEl 6dB 20dB 22d8 19d8 18dB previous reading

Input signal 1-23pV 1.6pV 3.7pV 6-5pV 80pV 4.4mV 28rnV 120mV

Later Relative receiver increase to 2dB 7dB 5dB 22dB 35dB 16dB 13dB previous reading

S-meter calibration Crossmodulation was evaluated with the TR7 switched to a.m.. As for S-metcr calibration at I4MHz is shown in Table 2. There appears to be a the blocking measurement, generator A was set on tune at a level of 500pV considerable difference between the earlier and later models and addi- rf output and modulated with a I kHz audio tone to a depth of 30 per cent. tional measurements made by the Drake distributors differ from both of The af gain control was set to give 100m W audio output power, and the these. The S-meter calibration does not vary significantly across the fre- modulation then turned off. Generator 13 was then set 50kHz off frequen- quency range. cy and modulated with a I kHz audio torte to a depth of 30 per cent. The level was increased until - 20dB crossmodulation resulted in an audio out- ACC performance put of ImW. This occurred at a level of about 500mV. The age threshold was found by slowly increasing the input signal until the Reciprocal mixing is caused by the noise spectrum of the local oscillator. af output ceased to rise linearly with the input. This was as follows: With the TR7 switched to ssb, generator A was set on tune at a level of 25µV and the audio output set to 100m W. Generator A was then turned Frequency AGC threshold 3.5MHz 1•75pV off and generator B turned on. Generator B was set off tune and its level 10MHz 1•75pV adjusted to give a noise output of ImW. This level was as follows: 21MHz 1. 4pV 30MHz 1 • 41.4V Frequency offset Level 10kHz 25rnV A 100cIB increase in input signal level above the age threshold resulted in a 20kHz 45mV 3dB increase in audio output. Similarly, a 106dB increase in input signal 50kHz 200mv level above the age threshold resulted in a 4d13 increase in audio output. Third-order intermodulation distortion is normally measured with a The attack time was measured as Ins, and decay times as 0.2s in the fast signal spacing of 20kHz. However, due to the reciprocal mixing results, mode or 0.5s in the slow mode. AGC pumping occurred at high signal this test was carried out with a spacing of 50kHz. A reference signal of levels. The age performance was evaluated on the earlier set only. 0.5 e was first injected into the TR7, and the audio output set to 100m W. The two generators were then tuned off frequency by 50kHz and 100kHz Signal handling respectively, and the levels increased equally until an intermodulation pro- Signal handling was evaluated by measurements on blocking, duct was produced in the receiver passband with an audio level of 100m W. crossmodulation, reciprocal mixing and third-order intermodulation using This occurred at a level of 90dB above 0-5aV. This corresponds to a third- the test arrangement shown in Fig 2. Both transceivers gave similar results order intercept point of + 22dBm. on all these measurements, and no substantial variation with frequency was found. Audio power output and distortion Blocking was evaluated with the TR7 switched to a.m.. Generator A was The audio power output was measured into a 4S2 load. Greater than 2W set on tune at a level of 50001 r.f, output and modulated with a 1 kHz could be obtained with an input signal of 5irV. Total harmonic distortion audio tone to a depth of 30 per cent. The af gain control was set to give at 2W output power with a 500,/ signal was measured as eight per cent. 100m W audio output power. Generator B was then set 50kHz off frequen- cy, unmodulated, and its level increased until the audio output dropped by Frequency stability 3dtl. This occurred at a level of about IV. Frequency stability was excellent, remaining within 20011z after switch-on for a period of 2h. A detailed investigation was not carried out.

Transmitter measurements Power output and distortion The maximum power output front the transmitter is limited by the ale cir- cuitry. Incorrect alignment of the ale circuitry can result in powers in ex- cess of 180W and destruction of the power amplifier or instability. With the transceiver as supplied, Table 3 gives the power output obtained with the later transceiver. The cw power was measured with the carrier control at maximum. The power in ssb mode was measured as shown in Fig 2. Tones of 700Hz and 1,700Hz were applied to the microphone socket, and third-order intermodulation distortion products measured with respect to the amplitude of one tone of the two equal tone test signal. (Intermodula- lion products are often quoted with respect to p.e.. level, in which case the distortion levels will be 6dB lower, cg - 32(113 at 28MHz instead of - 26dB.) Increasing the audio level and driving hard into ale did not significantly degrade the ip performance.

Table 3. Transmitter measurements

Frequency CW power Two•tone power Third-order ips Third-order ips Max pep. at max p.e.p. at 100W pep. 1.8tV1Hz 110W 110W -31dB -- 33dB 3.511/1Hz 150W 135W -32dB -37dB 7MHz 120W 135W -31d8 -35dB 161r 1110 11 file 14MHz 114W 125W -29d8 - 33dB 21MHz 100W 100W - 30dB - 30:1B Bottom view of the TR7 with cover removed 28MHz 94W 100W - 26.d8 26c1B

524 RADIO COMMUNICATION June 1981 Audio response changing very rapid. Excellent audio quality reports were often received. The transmitter audio response was evaluated at 50W output power. The In common with all transceivers with broadband power amplifiers, to ob- 6dB points were 500Hz and 2.7kHz, and ripple in the passband was less tain full power it is important to keep the antenna vswr below 2:1. An atu than IdB. should be used on antenna systems where the vswr exceeds this figure. On receive, the most impressive feature is the wide dynamic range. Harmonies and spurious outputs Evening operation on 7MHz is always a testing time for any receiver, and Harmonics and spurious outputs were measured on cw at full power out- the TR7 passed with flying colours, yielding clean copy from weak stations put. The fourth harmonic and above were less than - 80dB in all cases. among the much stronger stations. On 28MHz there was no lack of sen- Band Spurli sitivity, and in most cases the internal spurii were inaudible. AGC pump- 1-8MHz Harmonics -45dB. Spurii less than -70dB ing was experienced on both receivers at times, and this should have been 3-5MHz Harmonics -62dB. Spurii less than -60dB designed out on a receiver of this quality. The passband tuning proved par- 7MHz Harmonics -52dB. Several spurii -45 to - 60dB ticularly useful on the crowded lower frequency bands. 14MHz Harmonics -5&113. Spurii less than -70dB 21MHz Harmonics -66dB. Spurii less than -62dB A power amplifier fault developed on the earlier transceiver during the 28MHz Harmonics -64dB. Spurii less than -53dB first year of operation. The pa board was replaced by the distributors, and The carrier suppression varied somewhat with time and temperature but fast and efficient service obtained. was generally around -45dB. The unwanted sideband suppression depends on audio frequency and was generally much better than - 60dB. This figure is academic as the unwanted sideband will be completely mask- Concluding remarks ed by intermodulation products. Both reviewers were impressed by the performance of this transceiver. Many of the problems obtained with early TR7s seem to have been solved. Power meter calibration The general coverage facility is useful, and the case of adding full transmit The rf power meter incorporated in the TR7 was checked for accuracy in coverage is particularly important considering the future introduction of the forward power mode only. The readings were obtained using the later three new amateur bands. (The later transceiver reviewed was already transceiver. equipped for general coverage transmit operation.) The TR7 comes complete with a 45-page operating manual. Although a TR7 reading obtained for block diagram and a basic description of the circuit functions are given, no Band 10W 20W 50W 100W 1.8MHz 4W 11W 44W 110W service details or circuit diagrams are included. A service manual is 3-5-21MHz 3-4W 8W 37W 90W available at a price of £18-50 incl VAT. Although this may sound expen- 28MHz 2.5W 6.5W 32W 74W sive, it is well worth the money and very comprehensive. It contains around 150 pages, with many clear fold-out diagrams and photographs. The current cost of the TR7 with digital readout and general coverage On the air results operation on receive is £1,035 incl VAT. The mains power supply, PS7, Both transceivers have been used under a variety of conditions, including costs £207 incl VAT. The earlier transceiver is the property of G3WTM. home station, portable, mobile and contest operating. The absence of a The later transceiver was kindly loaned by Radio Shack Ltd of North preselector and pa tuning controls makes operation simple and band London.

Thandar TM354 I.e.d. hand-held multimeter The TM354 is a very compact 3.5 digit, hand-held, pocket multimeter featuring a large 0-Sin liquid crystal display, 0.75 per cent basic accuracy, and 2,000h battery life from one 9V alkaline battery. The meter provides five functions in 14 ranges, permitting measurement of de volts (from 1mV to 1,000V), ac volts (from IV to 500V), dc current (from lirA to 2,000mA), resistance (from Ill to 2m11) plus diode check. Supplied with test prods and protective vinyl pouch, the TM354 is Thandar PKW-5000 eprom program mer designed and manufactured in England, carries a full one-year warranty, The PKW-5000 with eight-bit Z80 cpu and 16k dynamic r.a.m., will pro- and costs £39.95 plus VAT. Further details from Sinclair Electronics Ltd, gram almost all eproms from 4k byte to 32k byte, using the r.a.m. buffer London Road, St Ives, Huntingdon, Cambs PE17 4H.1. Tel (0480) 64646. method; a major feature is the simple selection of rom type by slide switch. The instrument is housed in a sturdy, compact case with a built-in power supply. Front panel legends are clearly presented, the I.e.d. display is large and bright, and these features together with the programming safety features (erase, check, verification etc), mean that the PKW-5000 can be used with confidence by beginner or expert. An optional board is available which can be quickly and easily installed by the user, enabling the instru- ment to interface with virtually any terminal or I/O. The PKW-5000 is available, ex-stock, at £799 plus VAT. Further details from Sinclair Electronics Ltd, London Road, St Ives, Huntingdon, Cambs PE17 4H.I. Tel (0480) 64646.

The Thandar PKW-5000 eprom programmer The Thandar TM354 digital multimeter

RADIO COMMUNICATION June 1981 525 vide a more appropriate supply voltage for the SL1640C when operating A vif up-converter for from a 9V battery: a supply of 9V is the absolute maximum recommended by the manufacturer. The PP3 battery and the printed circuit board used on the prototypes were retained in the RS Components plastic case by means of "Blutak", shortwave receivers which is obtainable from most stationers. This is excellent material for retaining lightweight components, thereby avoiding screw holes in the case and pcb. by R. LAPTHORN, BEng, G3XBIV1' Results achievable On completion, no alignment is required unless accurate crystal netting is desired. Both MSF Rugby on 60kHz and BBC Radio 4 on 200kHz should Introduction be receivable throughout the British Isles at good strength, so these may be The circuit to be described "up-converts" the fascinating 3-300kHz vlf/If used to adjust Cll. For example, if a 14MHz crystal is used, the receiver spectrum to any convenient shortwave range between approximately 3.5 should be tuned to 14. 200kHz and trimmer adjusted until the carrier of and 25MHz. It has excellent sensitivity and requires no adjustment other Radio 4 produces a zero beat. Time signals from MSF Rugby should then than optional crystal netting. Construction is straightforward using a be received on 14.060MHz. single sided printed circuit board. The prototypes were tested on a variety of antennas including a simple 30ft wire around the loft. Even this enabled many vlf stations to be copied, Circuit description including S9+ 60dB signals from MSF, OMA Czechoslovakia on 50kHz From the antenna the received vif signal is applied to the signal input of a sending time signals, GBR Rugby on 16kHz, and various OMEGA naviga- double-balanced mixer, ICI, via a broadband low-pass input filter C8, C9 tional beacons around the world between 10 and 14kHz. Certain natural and LI. This filter, which has a cut-off frequency of approximately emissions should be audible below 10kHz with an adequate antenna and 150kHz, attenuates high-level medium and shortwave signals and prevents an electrically quiet environment. them from overloading the mixer. Signals above the filter cut-off frequen- Many of the signals receivable are facsimile, high speed cw, or rtty cy will be received with reduced strength to beyond 300kHz. transmissions in the fixed and maritime services. Reception of these ser- Carrier injection to the mixer is provided by the output of a crystal con- vices is not permitted within the terms of the UK Amateur Sound Licence. trolled oscillator, TR I. However, reception of standard frequency transmissions is permitted and The SLI640C has an integral output load resistor with a voltage source these are plentiful at vif, where world-wide coverage is possible at all times output, pin 5, together with a low-impedance emitter-follower output, pin without ionospheric disturbance. 6, which is used in this converter. The manufacturer recommends that the emitter-follower output should not be used to drive capacitive loads, since Conclusions signal rectification can occur under such circumstances and result in When used with a selective shortwave receiver and a good antenna this waveform distortion and harmonic generation. In practice all the pro- converter provides a first-class vif receive facility. What we now require is totypes worked without problems when connected to various hf a limited amateur allocation at vlf to enable amateurs to address the transceivers and shortwave general coverage receivers which presented challenges of communicating over useful distances with electrically short non-reactive inputs of between 50 and 3002. The converter noise figure, antennas (L«1) and consequentially low radiated power. The possibility typically 10dB, is more then adequate at vif where external man-made and of such an allocation, regrettably, seems remote. atmospheric noise can severely limit the usable sensitivity. Because a double-balanced mixer has inherent rejection of the signal and carrier inputs at the output port, it is possible to receive signals which Acknowledgements produce an i.f. that is extremely close to the local oscillator frequency. The writer wishes to thank Pye Telecom Ltd for the use of their excellent This is a distinct advantage at vif where the lowest input frequency may laboratory facilities while testing the prototypes. only be a few kilohertz. In practice it should be possible to tune down to approximately 3kHz (100,000m) before the local oscillator overloads most Bibliography ssb receivers. A receiver possessing a narrow cw crystal filter should main- Ill Linear Integrated Circuit Data Rook—Plessey Semiconductors Ltd. tain good performance to below IkHz (300,000m). 121 VLF Radio Engineering, A. D. Watt. Pergamon Monograph 1967. Using the single sided printed circuit layout provided, construction This contains a chart showing most vif transmitters operational at that should present no problems. Holes are provided for two base configura- time and remains relatively accurate. tions for TRI, and the metal can SL640C double balanced mixer may be 131 "Radio Communication at frequencies below 10kHz", R. Lapthorn, used in place of the SLI640C if the leads are preformed. BEng, G3XI3M —Radio Communication April 1975. The LED, which is not mounted on the pcb, provides an indication that 141 Whistlers and Related Ionospheric Phenomena, Robert A. Helliwell, the converter is switched on, and conveniently drops about 1.6V to pro- Stamford Univ Press 1965.

j13F197 Output 2 R5 LEW c e b 100J2

1..C5 6F224 BF273 b ec 1-14 R1 27k 4

I Cl 9v

15 7 6 8 Fig 2. PCB track layout Itrack sirJel actual size R2 X1 7 .,....C11 27k .3i5p to C2 R4 Re 10V 47p 3.3k 1-2k

Fig 1. Circuit diagra m

indicates typical C8 C9 dc voltages —1- 10n 1 T 1On C7 0.1 100F,F-I Input •37 Spring Close. Burwell, Cambs CBS UHF.

526 RADIO COMMUNICATION June 1981 Components list Output to BNC socket R1,2 271t1/ C1,2 47pF ceramic R3 2.2kft C3 120pF ceramic 114 3.3kft C4 1nF ceramic R5 100(2 C5,6,7 0- 1uF ceramic 116 1.21(11 C8,9 lOnF ceramic (All 0-25W 10%) C10 1014F tantalum 10V wkg 1 L1 100uH choke C11 3.5 13pf trimmer (for xtal -L netting if required). R2 TR1, R3 xr ' [II .11. LED 1 Light emitting diode C2 CS Input from BF197. BF273, or similar RL -t- + e. wander socket TRI 'Cl SL1640C or SL640C double-balanced modulators •• =1-• (Plessey) xl HC18/U or HC25/U miniature fundamental crystal between 3-5 and 25MHz To LE D1 ' 77C1V I 9V battery PP3 or similar Case RS Components, stock No 508-914 ABS plastic 0 Fig 3. Component layout

+9V o A simple add-on unit for C5 14.7p 20., C2 0.1 Audio Inutile -1i counting audio frequencies tin 1 • —.16 1 16 16 15 2 15 2 15 14 14 by I. BRAITHWAITE, G4C012 3 14 4 13 4_ 713- 1 4 13 12 +10 12 +10 12 6 rr HE need occasionally arises in experimental work for an accurate 10 10 7 lo measurement of audio frequency, and where a frequency counter is Cl 9 9 9 e2p used there are two common methods of arriving at an accurate answer: 'Cl IC2 IC3 4046 R3 4017 4017 1. Use of a long gate lime. 1k For example, a lOs gate time will allow a frequency of several hundred RI hertz to be measured to well within I Hz, while a Is gate time will produce 1 k 'C3 OV an uncertainty of one count, ie 1Hz. This method is therefore of little use T1•70 where input signals disappear or change in frequency within the gate time. 2. Use of the counter in its timer mode. VCO output *Output to Counter Here the roles of input signal and counter crystal are reversed. The input .1001in signal is used to open and close the gate while the counter's crystal 101100 oscillator is counted. This gives an accurate reading of period after as little as one cycle of input frequency. Calculation of reciprocals is required to Fig 2. Circuit diagram convert periods to frequencies. While many amateurs own or have access to a counter, these are often Circuit details (Fig 2) built with rf measurement in mind and have too short a gate time for audio The phase-locked loop contains a division ratio of 100, so the counter work, and no time mode. receives a signal frequency 100 times that of the input. The vco and phase A solution now quite common in instrumentation is to use phase-locked multiplication. The multiplying phase-locked loop is shown in Fig I. The detector are contained within the cmos 4046 ic. The maximum vco fre- quency being somewhat above IMHz, the maximum input frequency is voltage controlled oscillator (veo) is divided in frequency and compared with the input frequency in the phase detector. The output of the phase around 10kHz. Above this, many counters can be used directly and accurately. detector is filtered and applied to the vco so that it locks to a multiple of The loop bandwidth is a compromise between noise rejection and seul- the input frequency. The vco can be counted accurately with a short gate ing time. It is determined by R2, R3 and C3, and experimentation with the time, and this is the principle used in the add-on multiplier. values may be worthwhile.

Voltage-controlled Frequency divider oscillator ( VCO) (divides by integer N)

When loOP IS locked. f ose -i-N losc fin N To input The VCO output is thus of Fig 2 a multiple of the Input frequency

Oscillator f osc control voltage -Tr

Fig 3. Input amplifier

f_In Input or reference 0 'm frequency fin Construction

Loop I ilter Phase detector The prototype was built as an add-on unit on Veroboard and housed in a plastic box with a screened lead between the multiplier and countet. A PP3

Fig 1, Multiplying phase-locked loop battery is adequate as power supply. The 4046 will work with input signals in the several hundred millivolt range. If greater sensitivity is required, an input stage as shown in Fig 3 is 28 Oxford Avenue, St Albans, Hens Al.I 5NS. suggested.

RADIO COMMUNICATION June 1981 527 The ten-turn "chopstick" 'e•• - - --••••• 1

• helical: a high gain antenna --.-

.: ...... • fOIM10...... • . 7..... for satellite work A.Ort...... l I. . , , • •

by COLIN RICHARDS, 9M2CR'

The author, 9M2CR, with the completed helical

Introduction in satellite work, the never-ending search is for forward gain. It is a task has neatness, high gain, wide bandwidth and circular polarization all in that jumps to the forefront with the approach of a new breed of satellite, one! Scanning the handbooks for design on helicals, information sug- the Phase 3. Phase 3 will be put into a -pseudo-synchronous" orbit, which gested that a ten-turn helix might be promising: a gain of 14{1B would per- means that it will offer many of the advantages of commercial syn- suade the author's IOW output to masquerade as 300W, and a beamwidth chronous satellites. It will swing around the bottom of the globe at a low of 40° should not be too awkward to point. The boom length at 435MHz perigee of 1,500km and then hurtle out to an apogee of 36,000km —and would be about 6ft, with a reflector 28in square. These seemed here is the bonus—its movement relative to an earth station for the four manageable dimensions. But what to use for the helix? How to form it? hours spanning this apogee will be small. For four hours there will be an How to keep it in shape? All pertinent questions for this particular QTH, almost-stationary satellite covering almost half the globe. For the first for the nearest parts or material stores were some 70 miles away. time, radio amateurs will be able to communicate on a world-wide basis The boom was no problem. A 6ft 4in length of I by 0.5in meranti using vhf and uhf, thus avoiding many of the problems of hf propagation. timber, good and straight, looked just about right—with the lin edge ver- What is more, doppler shift at the apogee will be very slight, so that the tical to avoid any bending. (As it happened, the antenna itself turned out skilful searching and re-tuning so essential with low-orbit satellites will no to be very light, and was easily supported by the I by 0.5in). But what longer be required. about the helix and spacers? Copper tubing was unobtainable; in any case However, there is a price to be paid for these advantages. The satellite's it would have been expensive, heavy and difficult to shape. Coaxial cable path length at apogee is virtually the same as that for commercial syn- had been suggested, so why not RG58? The outer screen would simulate a chronous satellites. The commercial users counter this path loss by using tubular conductor, the inner conductor is not needed but could be soldered giant 30m dishes and low-noise amplifiers on receive which are cooled in to the screen at each end, and high grade coaxial has a tinned, close-mesh liquid helium. No amateur can compete with this; but latest estimates for screen with an excellent weatherproof sheath, all of which would be ideal. Phase 3 suggest that amateurs can manage with an crp of 500W, a A 25ft length was promptly hunted out. tolerably modest figure. Of course, a 500W final is out of the question for Spacers were now the problem. Most handbooks showed three spacers most amateurs, so that gain must be found elsewhere, notably from the per complete turn of the helix, each spacer being set at a 120° angle to the antenna system. last. Since the boom was rectangular, it seemed more sensible to opt for four spacers per turn, and to put them at 90° settings. The original plan Construction was to use 0•25in diameter plastic rod or wood dowel for the spacers, but Phase 3 uplink will be centred on 435 • 215MHz, and will require clockwise nothing remotely resembling such material was available locally. Ponder- circular polarization. The question is how to make a high-gain antenna ing the problem over an oriental meal, I suddenly saw she answer in my with circular polarization, which can be hoisted into the air and pointed in hand—chopsticks! the right direction without too much trouble? Yagis—crossed and Chopsticks are available in a wide variety of designs and material in phased—offer one solution, but at 435MHz the phasing harness could pre- Malaysia: we chose simple, wooden, everyday chopsticks, undecorated, sent problems, as could impedance matching. So why not a helical, which sold in bundles of 20 for US 25 cents a bundle. As with most chopsticks, the lower half is of circular, tapered cross-section—merging into a rec- tangular shape for the upper half, which was ideal. We marked the boom at 1-7in intervals, and drilled holes 0-325 diameter—each at right angles to the last for the boom's entire length. The boom was long enough to allow 3 to 4in to stick through the reflector for clamping purposes. A 3.4in piece of the same boom material (1 by 0' Sin) was fixed to the boom at the reflector end, and the I .7in intervals were measured from this, as shown in Fig I. A drop of glue was put into each drilled hole, and the chopsticks were pushed in one by one until they were wedged tightly. A double-check was made to ensure they were put in with a clockwise spiral, as viewed from the reflector forward (je from the back of the beam). When giving the final push, each chopstick was twisted so that the square sides were roughly in line with the path that the RG58 helix would take. This made it easier to file a small U-shaped depression in the top allowing the RG58 to sit neatly. Chopsticks are generally about 10in long, and when pushed through the boom, about 4in protruded on the other side. These bits were carefully sawn off. The helix diameter is 9in, so a mark was made on the last four spacers at each end of the boom, at a point 4.5in from the centre-line of The ten-turn "chopstick - helical aloft. The az-el steerable array includes a cross-Yagl for 145MHz, and a three element Yogi for 29•4MHz downlinks the boom. A fine hole was drilled at these marker points, and thread strung along from first to last spacer in each of the four rows. This enabled the other spacers to be marked to show where they should be cut off. After • 73 islam Panlai, Port Dickson, Malaysia trimming, the tops were filed into U-shaped depressions in line with the

528 RADIO COMMUNICATION June 1981 Eift 4in (2.8A) boo m

Reflector

14.n Feed .mpedance 140R 15058 coaxial cable Chopst,c spacers

Matching section

9In

a Spacer interval a = P = 6.0 in = 435 MHz = 1.7 in 50D coaxial 4 = 27.15.n cable feeder

Fig 1. Dimensions of the antenna. Gain 13-14dB, beamwidth 40°

helix path. A small hole was then drilled 0. I 25in below the tip, so that a with two stainless steel hose clips around the coach-bolts and boom. The piece of waxed thread could be used to bind the RG58 helix in place. reflector weighed about 81b, whereas the antenna-plus-boom weighed only One end of the 25ft length of RG58 was bared for 0.5in. the sheath and 21b. A plywood bracket was therefore fitted at the balance point, just a dielectric removed, and the screen and centre conductor twisted together few inches from the reflector. Minor dents in the RG58 helix were pushed and soldered. Starting with this end, the RG58 was bound to the short gently into shape, and the ten-turn "chopstick" helical was almost ready straight end section (3.4in) next to the reflector position. The soldered tip for hoisting aloft! was placed so that it would mate with the centre terminal of an SO-239 There still remained the question of matching to a 500 feeder. The feed socket which would be mounted on the back of the reflector. The RG58 impedance of a helical antenna of this design is near enough 1400 (this helix was then wound around the spacers carefully, one at a time, binding stays the same, regardless of the number of turns in the helix). A quarter- in each spacer before moving to the next. In this way it was possible to wave matching section should therefore have an impedance of about 8412. ensure that an even, circular spiral was created, with no bulges or flat sec- The nearest coaxial is RG62, which has an impedance of 9312. A quarter tions. As we neared the tenth turn, there was about 8in of surplus RG58. wavelength at 435MHz is 6.8in and the velocity factor brings this down to This was cut off, the end trimmed, and the outer screen and inner conduc- 5.7in. (There is a trap here: solid-dielectric coaxial like RG8 or RG58 has a tor soldered together as at the start of the helix. The thread bindings were velocity factor of 0.66, but RG62 is partly air-spaced and the factor is touched with glue, and the boom and chopsticks given a coat of clear 0.84). After many "cuts and tries", the swr was brought down to I :1 • l. varnish and set aside to dry. Results? When used as an uplink antenna on Oscar 7 mode B, signal Half-inch squared meshed gi screen was used for the reflector, and a reports have been encouraging. Downlink on mode J the antenna can copy 28in square cut out and edged with 0.5 by 0•5in aluminium angle. A stations right down to the horizon. The antenna seems to work! small, sturdy aluminium plate was used as a centre mount for the reflector (it was in fact an old door-lock plate!). An aperture, I by 0.5in was cut in This article has previously been published in Orbit and Amateur Radio. the centre to allow the boom end to fit through and protrude 4in on the other side of the reflector. A hole was drilled above and below this aper- ture for a 3 by 0.25 coach bolt. The bolts were firmly screwed to the plate, with most of their length also protruding to the rear of the reflector. Two more lengths of aluminium angle (0.5 by 0.5in) were screwed across the plate vertically to make the reflector rigid. The SO-239 socket was fitted to the plate, facing backwards with its centre terminal aligned with the end of the helix at section A. The antenna boom was then pushed through the reflector mounting plate, carefully squared up, and fixed firmly in place

Getting to kno w double-balanced mixers Hatfield Instruments, who design and manufacture double-balanced mix- ers, have published this 18-page booklet on the theory and application of mixers for engineers and circuit designers. It describes in practical terms how mixers work, their important parameters and limitations, and the way they can be used in several different circuit applications such as frequency converters, phase detectors, attenuators and modulators. Being generously illustrated and containing references for further reading it will be very useful to design engineers and is available free of charge from Hatfield Instruments, Burrington Way. Plymouth, Devon PL5 3LZ.

A mateur Radio Logbook

The standard fixed-station logbook. The wire binding gives easy fold-back to save space and the large A4 size gives plenty of space for remarks. 96 pages: vvirebound; 210 by 297mm

The chopsticks form light, strong and durable spacers

RADIO COMMUNICATION June 1981 529 the ground plane becomes less important, the bandwidth is increased and all dimensions become more tolerant etc. The elements may be stretched to 2,3 or 4 times the length of a resonant TECHNICAL wire dipole or unipole: Fig 2. For a centre-fed dipole using 50,12 coaxial cable, a A/2 section (26-Sin or 673mm) of RG58-U or RG-174 cable is needed to reverse the phase of the lower section, and a small pi-network to TOPICS match the coaxial cable. The 2 x dipole does not need the pi-network and is easy to make at a first attempt. Fig 2(c) shows a 2m-high centre-fed dipole that can form an excellent vertically-polarized or horizontally- Pat Haw er, G3VA ] polarized indoor antenna for flat dwellers. The 4x dipole, Fig 2(d) provides an even more satisfactory antenna which, for best results, should be erected as high as possible: it will work HIS month we consider why and how to stretch your 144MHz anten- well even when spaced only 6in (152mm) from a vertical pipe mast, with Tnas; current hf transceivers coping with those very strong signals; the pi-network adjusted for minimum swr when the antenna is in position. high stability inductors for the vfo; solid-state and the ht transmitter, and The coaxial feeder cable can be brought down inside the pipe mast. why parasitics are still a problem in transistor amplifiers; the "simplest" Because of the strong broadside radiation, care should be taken to erect valve transceiver; what happens to signals at the midnight hour . . . and the element vertically. more besides. With so much to pack in, it's straight down to item one. Table 1 shows the dimensions, sizes of capacitors and approximate in: put impedances; capacitcrrs can be made from 0.062in (1.588mm) double- Stretched vhf/hf antennas sided glass-fibre printed circuit board which has a capacitance of 3pF/cm' In the RSGB Bulletin of July 1961, F. J. ("Dud") Charman, G6CJ, etc. Capacitors should be cut rather longer than required and then filed described an important, though very little used, fundamental principle of down to the correct size (check with vernier calipers or by other means to antennas that can offer some significant advantages: this was the principle ensure that they are of the correct capacitance). The element is made from of capacitively-loaded or "stretched" antennas. Because most amateur hf 1mm diameter wire (or I8BS) with each 30° section 166mm in length. stations suffer from space limitations, it has always been difficult to per- The whole antenna, plus the A/2 phasing section where appropriate, can suade many people that the unique properties of stretched elements make be mounted inside electricians' plastic conduit (20mm) or pvc water pipe this sometimes a worthwhile and valuable approach. For the stretched (I5mm), the latter being the more rigid, with "T" fittings and junction element, which may be several times the length of a conventional wire boxes as required. This is an inexpensive form or construction; ends can be element for the same band, has not only considerably increased radiation pulled tight on fishing line through corks in the top and bottom of the con- resistance, resulting in broadband operation and minimizing earth losses duit or pipe. Very thin RG174 cable is useful for forming the A/2 phasing when used as a monopole, but also is hardly affected by the close sections. proximity of normal (unloaded) wires. While the above dimensions will enable stretched antennas to be con- G6CJ showed that it is possible to make hf elements stretched by a fac- structed without the need for design calculations, VK5NN provides the tor of from two to four times by using low-impedance balanced twin following notes for those wishing to calculate suitable capacitance values feeder, with loading capacitors formed from overlapping sections of the etc. feeder. His information relating to these antennas has been reproduced in (1) For 1mm diameter wire L/4D = 1016 for a 144MHz dipole. a number of editions of Amateur Radio Techniques (cg 7th edn, pp (2) The characteristic impedance of this wire is then: 303-5). Capacitively-loaded elements have been used in recent years in = 120 (In L/4D - 2.55) = 525n) derived from ARRL Antenna Hand- large commercial point-to-point/broadcasting arrays, and experimental book with In being the natural log, as explained in calculator instruction work has been reported on several occasions on uhf and microwave anten- manuals. nas, but little evidence has come my way of this principle being used by (3) Z.a is predominantly inductive, so for a 166mm wire XL = 525 tan amateurs; as far as is known ART remains the only book seeking to keep 30° = 30012. this idea going. (4) For a 2 x stretch, half of this, or in other words 15012 of capacitive It was therefore particularly interesting to receive a letter from Phil reactance is required (ie 7-2pF as shown in Table 1). Williams, VK5NN, indicating that he has been doing a lot of good work (5) Similarly, for a 4 x stretch, 0.75 of the reactance is neutralized; that investigating the use of this technique at 144MHz (and hf) and that it has is, 22512 or 4.8pF. yielded "remarkably good results". VK5NN gave a lecture/demonstration With a handheld scientific calculator you can play with these figures and of his work in Adelaide in September 1980, and the following notes are come up with your own design. But VK5NN adds the warning to use thin partly based on an account of this lecture published in the "VK5" journal. wires or you may run out of reactance; the designs will then not work out His work has aroused the interest of a number of local amateurs, par- (ie avoid metal rods and tubes unless you are quite sure you know all about ticularly those concerned with the development of low-cost verticals and :heir impedances). ground-plane antennas for 144MHz fm and repeater operation. One local The pi-networks can be made from small plastic or ceramic trimmers. amateur is using a stretched element concealed in a pvc sewer pipe in an Use 4-I5pF on the antenna side and 5-30pF on the 5012 cable side. The coil "antenna-sensitive" housing estate. VK5NN is now extending his work to can be made with about three or four turns of 18g wire about 0.25in hf, using, for example, "two x unipole" antennas for single-hop work on (6-3mm) diameter. These parts will all mount on a small piece of pcb 3-5/7/14MHz, while operating portable and stationary-mobile in remote about 15mm wide inside the plastic pipe or junction box, with small holes parts of Australia; in this case using loading capacitors moulded in hard- for adjustment. Try different coil sizes until you can trim the swr down w setting epoxy putty in a shape that allows the antenna to be readily pulled near unity using the two capacitors; if you cannot achieve unity swr or one up through trees. He has also used stretched elements in vhf tv Band 3 trimmer is at the limit of adjustment, try a larger or smaller coil until you antennas. get the result you want. He is now testing phased and stacked vhf arrays with "flat" phasing VK5NN briefly mentions his hf antennas. He has a 6611 (20.11m) lines, and intends to look at the idea of using stretched elements better 7MHz unipole with six sections each lift (3.35m) long and five 138pF matched to open-wire feeders. He would be interested to hear from other loading capacitors. Used horizontally about 8ft (2.43m) above ground, it readers who may have investigated this type of antenna (P. M. Williams, can be end fed as a portable antenna from equipment such as the 40 Hyland Terrace, Rosslyn Park, 5072, South Australia). TS-120V, using the vehicle as a counterpoise earth.

144MHz stretched antennas VK5NN has developed a family of stretched dipoles and unipoles for 166 m m 144MHz based on inserting small capacitors every 30° of length (every A/12, ie every 166mm); this form of loading neutralizes a proportion of the Solder

inductance of the antenna element and so extends its resonant length (Fig Wire size . B & S 18g I). This has the effect of increasing the aperture and input impedance of or 19s wg the element and reduces the Q and the angle between the 3dB points on the See text for capacitor details polar diagram. A vertical element of this type radiates strongly broadside (in the horizontal plane), and is less affected by surrounding metal wires or Fig 1. Showing how home-made pcb capacitors are inserted at 166mm inter. metal poles: Because of their higher input impedance the effectiveness of vals to form a "stretched" 144MHz unipole or dipole antenna

530 RADIO COMMUNICATION June 1981 Table 1. Dimensions, capacitances and approximate input However, information given in an article by R. P. Christiaanse, impedances PAOGM W in the Dutch Electron (February 1981, p83) provides at least a useful comparison of the measurements he has made on a number of cur- Stretch Reactance C PCB Input impedance No of capacitors rent hf transceivers, even though quite wide variations may be encountered factor O W (pF) capacitor Dipole Unipole Dipole Unipote between different samples of the same model. These measurements were (cm ') (Si) (Q) made with the ssb filter, using input frequencies of 14,200 and 14,220kHz 2 x 150 7.2 2-4 200 100 10 5 3 x 200 5.4 1-8 400 200 16 8 with two Boonton signal generators and a Hewlett-Packard combining 4 x 225 4.8 1.6 550 275 22 11 network providing 20dB of isolation between the generators etc. Model Noise floor Intercept Dynamic Two signals for nV (dBm) point range 1,.N imd dBm dB mV (dBm) TS830 80 - 135) -8 85 2 (-41) 7.2pF TS820 100 - 133) - 18.5 76 1 f -47-W TS180 60 - 137.51 - 26 74 0- 5 ( -53) TS120 100 - 133) - 14 79 1 ( -43.5) TS130 140 - 130) - 12 79 1.5 ( -43.5) 166 m m each section F1901 140 - 130) - 1 86 3-5 ( -36) F1107 140 - 130) -6 82 2•5 ( - 39) F1707 140 - 130) -6 82 2•5 ( -39) IC720 140 - 130) + 5 90 5 ( -33) Alda 500 - 119) +4 82 5 ( - 33) 4.8pF Such a table needs to be interpreted with some care since an appraisal of strong-signal performance, important though it is, does not of course tell 12 sections 166 m m you everything you need to know about how the receiver will perform in Ri 100/2- practice on the amateur bands. For example, the selectivity filters may broaden out at 50, 60, 70 or 80dB down, depending upon the ultimate re- 20in 20in jection of the filter and the amount of stray coupling when this is installed 13.25 in in the receiver; and this factor may invalidate an exceptionally good dynamic range: similarly reciprocal mixing. 4 trans- The table shows, as might be expected, that the more sensitive a receiver former from 7017 coaxial is, the more likely it is to have an intercept point in the negative dBm cable region; the all-round performance of the IC720 appears to be rela- 70 to 5012 .-,'" tively good, at least as far as can be determined from just this set of connection measurements. The real proof of a receiver is how it performs for you in 5- 30pF 4- 5pF 5017 coaxial the shack; I would still place subjective characteristics as every bit as cable feeder 5017 important as the objective measurements. (But see the TR7 figures in the coaxial cable technical review on pp522-525.) feeder

PI network detail High-stability inductors G. Ripley, G3KFW, while endeavouring to minimize the frequency drift of 4.8pF home-constructed vfo units, came to the conclusion—as others have done 166mm rie; 7117:¡; 707:i.1 in the past—that one of the most stubborn problems in all types of LC oscillators is the change of inductance with temperature. It seldom seems to prove possible, as often suggested, to compensate for this by means of 12 sections negative temperature-coefficient capacitors, such as the Oxley "tem- Phasing line patrimmer" or "thermotrimmer" devices. Results using such techniques 7.2pF 26'S in of RG58 166m m or R0174 often prove disappointing. In the 'thirties various ingenious forms of temperature-compensated in- ductors, mostly based on bimetal strips or rods, were sometimes used; a Phasing line notable example was the massive inductor of the old American Command 26'51n 50/7 coaxial cable TU5B transmitter tuning unit. However, this approach seems unsuited to RG58 or RG174 - modern applications, and G3KFW set about developing inductors which connect braids together would have much lower temperature coefficients than the normal vfo coil. He experimented with copper wire wound "hot" onto Pyrex glass test Pi. network tubes, although he found it difficult to achieve satisfactory ways of ter- Ri 275/7 — minating the winding until advised that (with care) it is possible to drill ., holes in these test tubes. 4 - 15pF While this project was under way he discovered that Oxley (Oxley 3 0r4 turns Developments Co Ltd, Ulverston, Cumbria, tel Ulverston (0229) 52621) 1/4 in dia market a range of high-stability metal-on-glass inductors intended for use 5- 30pF 12 sections 166m m o 6-8V stab

5017 coaxial 27k 1k 10k 27k at least 4.8pF cable feeder separation 60p 166 mm 12p Output 7,2pF 0C171 0C171 To tune 1.8 to 2MHz [1 2p1 Fig 2. Realization of various "stretched" 144MHz antennas. (a) 2x unipole (ground plane); (b) 4 x unipole; lc) 2 x dipole; and Id) 4 x dipole

10k 680$7 Ok T lOn

Strong-signal performance It is generally recognized that the measurement of the strong-signal hand- I 0+ ling performance of a receiver is a task that requires considerable care, ex- pertise and access to reliable test instruments; there is also still the problem Fig 3. 1.8 to 2MHz Franklin emitter-coupled vfo built by G3KFW in 1959 based that procedures have not been fully standardized. on a design by VE2113

RADIO COMMUNICATION June 1981 531 in professional telecommunications and precision instruments, but also other basic design factors are also mentioned: total device power dissipa- suitable for one-off high-stability vfo units employing a two-terminal tank tion should be at least twice the desired rf power output for maximum coil. These use borosilicate glass formers, silver alloy metallization and reliability; device ratings at least I - 2 times the required minimum power silver-plated copper leads. The coil of thick metal alloy is fused to the glass output of the system; and an efficient heatsink large enough to dissipate former for maximum stability. Typically they can provide a Q of 200 at the thermal energy should be used (although the TO-220 package provides 50MHz with a temperature coefficient not greater then ±2Oppm/°C. Ac- a better junction thermal coefficient than the metal package, a thin layer cording to the firm's leaflet some 50-60 different values of inductance, of thermal compound, such as silicone, is recommended). Other points from 0.07814H to 4-114H arc manufactured, but there are some preferred are: minimum common-lead inductance to maintain gain and bandwidth values which should be selected for one-off units. 1 do not know the cur- achieved using wrap-around foil earths or plated-through holes that con- rent prices but clearly these arc precision components that are bound to be duct from the top side of the circuit board to the ground-planed bottom quite costly in small quantities; nevertheless they would undoubtedly be side near matching capacitors; and because of the high inductance of the very useful for high-grade vfo units. centre lead, the package must be rf-earthed by means of the flange, so it is One form of two-terminal LC vfo is the Franklin. In 1969, G3KFW important that matched components be so placed that the shortest earth- found the emitter-coupled form originally suggested by VE2IB (77' Oc- return path is the one to the flange. tober 1968, p649) provided a useful basis for a small solid-state 1.8MHz An interesting lower-power plastic-packaged device capable of pro- transmitter based on pnp devices (AUY10 pa): Fig 3 shows the vfo. This viding about IW or so of rf output at 500MHz and usable up to about was built before he began to investigate the question of temperature 1,300MHz is the Motorola MRF559 with a copper-lead frame, a stripline coefficients for the inductor. configuration and a compact (0.2in (5mm) diameter, 0- lin (2.5mm) thick) plastic encapsulation, and with an fr of 3GHz. This device can be used as a doubler, tripler, driver or for a low-power final amplifier. Even - HF transmitters: solid state or valves? from a 7-5V supply and 50mW drive an output of almost 600mW should It may seem strange that someone who tries to provide reasonably be possible on 432MHz, the device is also suitable for the 934MHz cb forward-looking technical articles should still, in 1981, feel it necessary to allocation. A detailed article on this device appears in rf design insert a question mark in the above heading. For many amateurs, valves (November/December 1980). are already being looked upon as collectors' items. Increasingly, the once- popular types are designated as obsolete, while those that are still available show every sign of rapidly being priced out of the market. For those com- Transistor construction practices ing into amateur radio from other branches of electronics, valves must An article "Good rf construction practices and techniques" by H. O. seem almost as much a relic of the past as "spark". Granberg of Motorola (rf design, September/October 1980) delves into a Yet I suppose only a tiny minority of the hf transmitters heard on the number of basic design points for solid-state rf power amplification when bands are all-solid-state, though admittedly the percentage has risen ap- using bipolar devices. preciably in the past couple of years. And if one moves away from the On the question of device selection, it is pointed out that for a-given sup- factory-made black-box, then unquestionably it is still very inuch easier ply voltage the input impedances arc roughly equal for uhf at 10-15W, vhf for the kitchen-table, home-brewer to put together a medium- or high- at 35-40W, and hf at about 100W. Current rf devices are usually made for power hf or vhf amplifier based on valves. The degree of design expertise 12-5V, 28V and 50V operation; devices intended for high voltages can be required for the design and construction of a reliable solid-state rf power used at lower voltages but, of course, not vice versa. It is not recommend- amplifier, whether linear or Class C or D, is of a different order from that ed that a uhf or vhf device be used at hÉ, except at appreciably reduced for a valve stage: partly because of the very low input impedances, partly supply voltage and power level; even then the higher gain may cause because of the exercise of care in device selection, partly because of the stability problems. On the other hand, hf devices can be used successfully greater number of potential sources of instability (which can destroy the at vhf/uhf in applications where low-gain (of the order of 3-6dB) can be device), partly because of more demanding heatsinking, and partly tolerated. While many newer rf power transistors are specified as being because it is still so very easy to destroy an rf power transistor when it is capable of withstanding infinite load mismatches, under a variety of working anywhere near its maximum ratings. Admittedly there are today operating conditions, it should be noted that this applies only when maxi- quite a few amateurs (not only those who, in their alter ego, are profes- mum total dissipation is not exceeded (as can happen if the device goes in- sional design engineers) who are competent to tackle all these problems; to self-oscillation). In general the physical construction of solid-state rf but, for the majority of us, the design, construction and testing of a power circuits is much more critical than for valves due primarily to the modern broadband all-solid-state transmitter or transceiver, other than low input impedance levels involved. for QRP operation, is a pretty formidable adventure—something rather more than an acceptable challenge. Parasitic oscillation When it comes to the question of buying factory-made equipment, the In any discussion on solid-state rf amplification, the question of parasitic position is rather different; here the design "bugs" have (we hope) been oscillation and instability is bound to crop up. This problem has been con- ironed out for us. For mobile operation there is little doubt where the sidered several times in T7' but further information is to be found in a choice will fall; for domestic operation there are a number of questions detailed article by Nathan O. Sokai in rf design, November/December that are likely to be answered differently by different amateurs (a) will it be 1980. In his introductory remarks he writes: "In transistor rf power possible readily to obtain replacement parts throughout the anticipated amplifiers, parasitic oscillation can occur in three basic forms; each can be lifetime of the equipment? (b) how useful in practice will, for example, caused by several different phenomena. Remedial measures for one cause broadband characteristics prove to be? (c) how reliable will the equipment be in operational use, and (d) how easy will it be to clear simple faults? generally are ineffective against other causes. The subject is complicated, and cures may be difficult, but the reason for oscillation need not be mysterious." The real problem for amateur designers, of course, is that Plastic packaged rf transistors unlike parasitic oscillation in valve amplifiers (which can occur without The packaging of rf power transistors has traditionally involved metal- damaging the valve) with transistors such a condition may lead to im- ceramic stripline techniques, requiring gold and beryllium oxide with high- mediate self-destruction of quite expensive devices. There are indeed times temperature silver brazing and manual assembly. This has tended to keep when one is tempted to say "bring back the 807, all is forgiven!" To sum- the price high, particularly for devices suitable for powers of IOW or marize the article briefly: more. Recently several firms have introduced lower-cost plastic packages, Feedback in Class A or AB amplifiers: Oscillation caused by unintended both at high power and low power. linear-component feedback paths. Cures include: better earthing; better For example, Communications Transistor Corporation, which makes power-bus bypassing; electrostatic shielding; magnetic shielding (closed the high-power CTC devices, has marketed a line of devices in TO-220 high-conductivity loops between coupled inductors, ie toroids etc); better plastic packages. These devices have a wrap-around metallized layer layout to reduce parasitic inductance or capacitance; and adding resistive which, it is claimed, permits shorter internal emitter leads and so helps to loading to damp remaining undesired LC resonances (eg ferrite bead is ef- reduce parasitics. The I75MHz 30W devices cost only about half the fectively a low-value inductance shunted by a resistor). Oscillation at a previous price; plastic devices for 50MHz, 470MHz etc are also available, frequency higher or lower than the operating frequency may appear in its and a range of 40W and 80W devices intended foé a.m. transmitters work- own right or as a second signal imposed on the original. It may exist in the ing from 28V supplies is under development. According to Electronics (7 absence of drive, or only when drive is applied and may cease when drive is April 1981, pp130-2) design procedures remain essentially the same as for removed; or it may occur only at certain supply voltages etc. In other the metal-ceramic stripline devices; the same consideration should be given words this is basically similar to the problems that may, rather less to device selection, adequate heatsinking and earthing techniques. Some frequently, be encountered with high-gain valves.

532 RADIO COMMUNICATION June 1981 Parametric oscillation: This is basically a nonlinear effect of a type not Simple valve OAP transmitters normally encountered with valve amplifiers. It is due to the pumping of a Andy Swiffin, G80EG, was interested in VK5EK's "one-hour" 5W nonlinear reactance at a multiple of the oscillation frequency. This results triode-pentode valve transmitter (TT April). For those seeking to cap this in oscillation at a sub-harmonic of the required operating frequency. with a one-valve "hf transceiver", he recalls experimenting with a "fixed Cures include minimizing the nonlinear reactance (which is often the channel" design described by T. Holbert, VS6CQ, some 25 years ago in collector-base capacitance of the transistor) at some sacrifice of power Short Wove Magazine (September 1955, p356): see Fig 4. The mains ver- efficiency; alternatively the addition of resistive damping, or (at low sion used a single EF50 or 6AC7 high-gain rf pentode as a crystal oscillator frequencies) the addition of a "swamping" linear capacitance. transmitter with pi-network output, or on receive as a leaky-grid Interaction between output circuit and base-bias circuit: The "memory" regenerative detector (RV regeneration or reaction conirol). A battery- of a solid-state amplifier makes it possible for the operation in one rf cycle operated version used the old 3A4 or 1T4 miniature valves with two fila- to influence operation in a subsequent cycle. Although rather similar to ment chokes (100 turns 32swg close-wound on an old I W resistor) and parametric oscillation, in this form it need not necessarily be at an integer screen-grid keying: Fig 4(b). G80EG tried out the arrangement a few years sub-harmonic of the carrier frequency. Cures include adding resistive ago as a receiver and was convinced it would have functioned effectively as damping to the base-bias circuit, or fitting a lossy ferrite bead on the base a fixed-channel transmitter if he had then held a licence. choke lead at the earthy end; or avoiding similar time constants in the For transmit-only, but with the added facility of variable frequency base-bias circuit and the envelope response of the collector load network. operation, a very simple circuit was used by the Germans in one of the first Interaction between output and input circuits via thermal feedback: Since Afu (agent I ransmitters) in the second world war, packaged with batteries transistor temperature affects the rf properties of the transistor, and these and accessories in two shoulder-slung leather carrying cases. This was in turn affect the rf performance, yet another mechanism for interaction exists. Interaction between output and input circuits via base stored charge: N. O. Sokal shows that it is possible for such interaction to result in sub- oHT+200V harmonic oscillation. T1 Sid He sums up the situation as follows: "(1) The problem is complicated; I r ip il Phones there are many possible causes of oscillation, many of which involve nonlinear properties of the transistor. A given amplifier might oscillate in several different modes, under different sets of conditions. (2) Eliminate RFC ; 2.5mH the avoidable modes of oscillation by using good construction techniques. 20k 0.01 L1 (3) For every remaining oscillation there is a cause. Armed with some knowledge and persistence, you can determine the cause and probably can . 2'500p 7-500p Sis cure the oscillation. If other oscillations are found, you can probably cure EF50 6AC7 them, too. Good luck!" Sic This is all rather depressing to those who want to build a one-off RV amplifier with a minimum of test gear. No wonder some people still say "Thank goodness for valves". 100k :0-01 5 to 30P 0.01 :30P How much sporadic -E? Each summer, from about May to September, the wind-induced ions of the thin but highly reflective sporadic-E bring short-skip contacts with Crystal RFC 100k European stations on 21 and 28MHz, as well as the much sought-after 2.5mH contacts at distances up to about 2,000km on 50, 70 and, occasionally, 144MHz. But in many countries it impacts on the public at large primarily 1-. 1001 as a cause of interference to tv reception; though in the UK, with the Sib transfer of tv to uhf Bands 4 and 5, this is no longer a significant problem, and indeed sporadic-E has become a boon to dx-tv buffs. But in countries where most tv reception is on the vhf channels, sporadic-E is studied more (a) as a problem than an opportunity. 0 HT+ 90V In IEEE Spectrum (February 1981, pp52-5), E. K. Smith and E. W. 3A4 Davis present a detailed survey of wind-shear sporadic-E, including notes GI 03 on the very different incidence of these thin ionic layers in different parts A of the world. For example, in the peak May to August season in northern temperate latitudes, a specified degree of sporadic-E (defined as having a reflection coefficient exceeding — 30dB for a path length of 1,600km at 63MHz) exists, in a typical year, for rather over 0.3 per cent of the time in southern England, but rather less (over 0.2 per cent of the time) in the —' north of England and the south of Scotland, and less than 0.2 per cent of 7.-500p2 Ste the time in north-west Ireland and the north of Scotland. Yet there is some 20 times as much sporadic-E in parts of Japan! In North America, Canada has roughly the same amount of sporadic-E (about 0.3 per cent of the 0.01 RV time) as the UK, but this increases (as you go further south) to about 0.9 100k per cent of the time in southern USA and around one per cent in Mexico. The article acknowledges the assistance given during IGY by radio Nees amateurs and the ARRL in providing masses of data on sporadic-E pro- Key 100k d:M Crystal pagation on the 50MHz band: "The data gave an excellent portrayal of the 1 time behaviour of sporadic-E . . . amateur radio operators are the only S2 ones who welcome sporadic-E since it helps them increase their range." H T— The article indicates that vhf tv interference due to sporadic-E tends to L T— (b) occur most frequently at a range of about 1,650km, with reduced in- O LT+ terference time at ranges appreciably greater than or less than this distance. It is of course much to be hoped that when 405-line tv in the UK finally Fig 4. Extremely simple single.valve. fixed-channel hf transceivers in which a pentode valve doubles as keyed crystal-oscillator and regenerative detector. closes in 1986, it will prove possible for a 50MHz allocation to be made On receive the crystal acts as a high-O tuned input circuit: (a) using mains- available to UK amateurs. But this may need diplomatic action as there are type EF50 valve (miniature EF91 etc could be used with appropriate pin con- others already seeking allocations in this part of the spectrum: it is nections): lb) battery version using 344 or 114 1-5V miniature valves. Original- ly described by VS6CC1 in SVVM in 1955, such a rig could still be used for QRP therefore useful to be able to point to articles in professional journals such cw operation on 1-8, 3.5 or 7MHz (though additional of, amplification on as IEEE Spectrum that show how amateur operation has proved of value receive might be useful). Li wound on lin (25mm) diameter former: 15 turns in the planning of tv services! for 7MHz: 30 turns for 3.5MHz: and 60 turns for 1.8MHz

RADIO COMMUNICATION June 1981 533 thoughtful "put-down" letter from a professional propagation/antenna Key 1 -1- 0-002 expert disputing that such layer entrapment modes could be a frequent oc- 0+250V currence since the low loss of an entrapped signal implied that very little I- 1' - 1. signal could be escaping back to Earth, and so could be used only for RFC satellite-to-satellite communication. A logical enough viewpoint, but one —2e 33 turns that had not grasped the idea that "tilts" occur regularly in usefully "link- Coils are 7 71,0003 ed" positions. One tilt puts signals into an entrapped mode, and then at 1 In did some distant region, another tilt sends them back to Earth. 5 turns Crystal Over a century ago Lord Salisbury stated: "You should never trust ex- perts . . . they all require to have their strong wine diluted by a very large admixture of insipid commonsense." This dictum is often unfair, since the 4 0 unconventional ideas often come in the first place from those experts who 5 turns are not afraid of radical thoughts, though certainly they are then frequent- 30 5 turns ly condemned by the more conventional experts as oddballs! 20 Another blow at the conventional multihop theory of amateur dx seems 5 turns to have been struck by detailed observations of 7.3MHz signals transmit- 10 0-002 ted from Ottawa, Canada, to Sidmouth, Devon—a distance of 5 turns 5,212km —by Dr M. Lockwood and Dr V. B. Mitchell of the University of Exeter during 1976 and reported in The Radio & Electronic Engineer, Vol 50, No 11/12, 1980. For dx-minded amateurs, this work seems particularly significant since it highlights a different form of paired ionospheric tilts to those that give rise to the dawn/dusk grey-line and long-path dx, and the 0.0003 -250V unfolding phenomena of transequatorial hf/vhf dx. Their work shows that low-loss paths in the west-east direction are fink- ed with the mid-latitude or main trough in nocturnal F-layer densities that

%* *•41--0- were first noticed when examining the data from the Alouette I "top-side" 4.5V ionospheric sounder of the early 'sixties. It is now recognized that at local 0+ midnight a pronounced trough is a regular feature of the topside Fig 5. Complete circuit diagram (except for the missing resistor values) of an ionosphere of both hemispheres, of the order of 10° of latitude wide. The early second world war German "spy" transmitter. Taps were provided for F-layer peak is reduced by a factor of about four at the trough centre various lengths of antenna or for various frequencies, with the adjustment which moves towards the equator, becoming narrower at higher Kp index aided by a small indicator lamp which was then shorted-out in operation. With the crystal replaced by a short-circuited plug, it formed a self-excited values and giving it steeper walls. It would seem that this trough, under tunable transmitter over the range 4 to 8.51MHz. Complete equipment (no certain conditions, can cause a marked decrease in the path loss between receiver) carried in two black leather shoulder cases: transmitter, plus spare North America and the UK, causing the Canadian signals (and probably valve, key and antenna in one pack weighed about 4Ib (1.8kg). while the those from parts of the USA) to peak up, until they are suffering a path rather larger battery case weighed some 7Ib (3kg). In practice, although numbers of these equipments were infiltrated into the UK, virtually all came loss some decibels less than the calculated minimum. It seems likely that under the control of the XX (Double-cross) Committee and were used for such signals are then travelling on a single-hop path, although this has not deception and disinformation purposes. The equipment was designed before yet been fully proven. the days of miniature valves and layer batteries! I Wireless World February 1941) This particular report is concerned only with 7.3MHz transmissions from CHU (I kW, monopole antenna) received in Devon using a Beverage described in Wireless World, February 1941, after some agents apparently antenna, but one suspects that similar modes occur occasionally on l • 8 elected not to become part of the "double-cross" operations (or were un- and 3.5MHz and that this is one reason why amateur night-time low- suitable) and were executed. This transmitter used a Telefunken battery frequency dx is so often at variance with the standard CC1R propagation pentode, type KL2, with a directly heated filament consuming 0-27A at tables. 4 • 25V and with three 90V ht batteries. It operated over the range of about The paper is not an easy one to interpret in terms meaningful to amateur 4 to 8 • 5MHz either crystal-controlled, or self-excited when the-crystal was radio, but one fact stands out: the presence, due to a regular trough, of replaced by a shorting link. According to Wireless World, it gave a good anomalously low losses on a path along the length of the mid-latitude clean note at mid-range, although the report was very critical of the equip- trough that does not seem to occur on paths perpendicular to it: Doppler ment in other ways. Battery replacement must have proved difficult in shift measurements support the view that there are exceptionally large, wartime, apart from the weight problem! regular shifts at these times. The authors state: "This suggests the trough is supporting a low-loss 2F2 mode or a chordal-hop mode at these times." DX in the trough My bet is firmly on chordal hop—a runner that 20 years ago was regarded For centuries science has progressed by great minds constructing powerful as a rank outsider! theories and then attempting to confirm them experimentally. The prob- Equally significant was the remarkable discovery by SV1DH in Athens lem has been that as knowledge advances further many of the more credi- that 50 and I44MHz signals received from southern Africa on 16 February ble theories begin to crumble around the edges, but by then the original could be heard only when his beam was pointing north. This suggests theories may have become so firmly established within the educational strongly that the signals were arriving via the long path, and appears process that it becomes almost a revolutionary act even to question them, to be the first recorded instance of I 44MHz transequatorial propagation just as they sparked off great antagonism when they were first propound- travelling along such a route. ed: witness the heat generated today when anyone questions Darwin's theory of evolution or Einstein's theories of relativity. Using the 7660 ic This new-theory/established-theory/doubted-theory process applies, it The requirement for positive and negative power supplies when using often seems, to hf radio propagation. Virtually every text book still states equipment or instruments containing ic op-amps etc can present problems. confidently that "one hop" reflection from the F2 layer is limited to a One useful way of overcoming these with either mains or battery operated range of under 4,000km, and that to cover greater distances requires a systems has become available with the introduction last year of the Intelsil series of hops such as 2F2 and 3F2 transmission modes, based on the ICL7660 positive-to-negative voltage converter. This device is a complete, discoveries of the 'twenties and 'thirties. Yet it is now over 20 years since high-efficiency, dc-dc converter that provides a negative dc line balanced the observations of Albrecht (DL3EC/VK3AHH), Villard, Yeh etc in- to the positive input line, so that both are available from a single battery. dicated that while multihop modes certainly occur, low power transmis- The technique is not unlike dc-dc conversion systems previously described sions, such as those from radio amateurs, depend very often on modes of in TT based on discrete devices, or using the "all-purpose" 555 ic timer propagation that have not suffered intermediate ground reflection losses: device plus some discrete components. chordal hop, layer entrapment, "whispering gallery", "round-the-world" The ICL7660 can also be used as a high-efficiency voltage splitter that modes etc, into which signals are launched by tilts in the ionospheric virtually eliminates the considerable power losses of conventional poten- layers. tial divider resistor networks. For example, with a stable 9V supply an out- I remember when, in the early 'sixties, I reported the idea that signals put of 4.5V±O• 1 per cent can be achieved at up to 80mA with ap optimum propagated in this manner could exhibit remarkably low path losses (and efficiency of 98 per cent at lOrnA load: Fig 6. This is achieved simply by sometimes travelled more than once around the globe) I received a earthing pin 5 (normally the V., load) and using the earthed lead at pin 3

534 RADIO COMMUNICATION June 1981 L'N — 4 turns 3mm Vd Hamlin NIDRR-4

k— 2mm dia wire 1 Supply ill To regulator Illm (See text ) ± 1 op Le 1 V+ Vow. —2-- DI

Fig 6. Use of the 7660 positive-to-negative dc de converter device as a high. Fig 8. Use of a reed relay to provide low-cost "over-current" protection. With efficiency voltage splitter this reed a four-turn current sensing coil will close the relay contacts at about 5A as the output. It may be advisable to connect a I MII resistor between pin 6 pl 34) uses a reed relay as a remote current-sensing device. In the arrange- and earth to ensure start-up for current-sinking applications. Power con- ment of Fig 8 using an energizing coil L consisting of just a few turns, the version efficiency is better than 80 per cent with a 6V supply for loads reed switch activates a shunt formed by the light-emitting diode, RI and from 0•5mA to 80mA. This arrangement was described by David Bingham of Intersil in Electronics, July 1980, p130. the zener diode. His energizing coil consists of four turns of No 12 gauge wire, and closes at 5A, but other numbers of turns could be used to pro- A sophisticated form of balanced supply with accurately regulated out- vide the required current protection. Triggering causes the output voltage put voltages (for example -.1:5V) can be achieved with the 7660 in conjunc- to drop to zero until the line current is reduced and the reset switch tion with recently-introduced cmos ic regulators, Intersil types ICL7663 depressed. The author also indicates that reed relays can be used for inex- and 7664, as shown in Fig 7. These regulators draw only about 3 •51/A pensive fault detection in such applications as car turn-signals/stoplights quiescent current with a 9V input (4,4A with I5V) and will regulate up to 40mA; they do not drop out until the 9V battery drops below 6V. In this etc. G8RSD mentions that Doram now stocks a range of 3W and 9W wire- arrangement the 10kHz internal oscillator of the 7660 is slowed to about wound resistors in such values as 0.1f2, 0. 1612 and 0212 to form current- 'kHz by means of Cosc (100pF) and using a 100pF capacitor. Regulated sharing resistors in high-current power supplies using several pass tran- output voltages are determined by the ratios R2/R1 and R4/R3. The 47pF sistors. He also mentions that a firm, Brian J. Reed of Battersea, has a input capacitors prevent instability and should always be fitted. This cir- useful line in high-power zener diodes at about 20p for IOW types and cuit diagram is reproduced from Electronic Design 31 March 1981, under 50p for 20W; such diodes can be useful for protecting psus by blow- p175-7. ing a fuse in the manner suggested several times in 77. A new Motorola MC3359 low-power fm i.f. ic device is intended for use I CL7663 with an external 455kHz ceramic filter to provide the second conversion SENSE section of nbfm receivers etc. It includes oscillator, mixer, limiting RCL +5V amplifier, afc, quadrature detector, squelch, scan control, active filters vouj GND Vet and mute switch. It has an I8-pin plastic dual-in-line package and can pro- R2 vide 700mV af output from about 2.1.1V input with a current drain of only ICL7660 ‘.1 about 3mA from a 6V dc supply. 1 47n trIr TT (June/July 1980, p649), with a follow-up in October 1980, p1038) con -r 7 R1 discussed the use of self-adhesive Teflon tape to protect antenna beam 100p I-- elements against ice build-up. In QST (January 1981, p44), John Ferguson, W IIIM, suggests an alternative method of applying a Teflon coating. He points out that (at least in the USA) Teflon Coating Product R4 No 82808 is sold in I6oz spray cans (H. W. Chesterton Co, Middlesex Industrial Park, Stoneham, MA 02190, USA). This is probably also 100 / 1 4 7n Ic available in the UK, and contains an acrylic carrier and provides a slippery DI R3 1N4148 ONO VsEt coating for surface protection and lubrication; it is resistant to water, mild Vout I o acids and alkalis. Price per can in the USA is about $5. Rtt —5V W I HHF (QST January 1981, p46) finds it much easier to use a pencil soldering iron with a curved rather than a straight tip. He also suggests IC L7 684 that to avoid burning wiring or small parts when working in cramped areas of equipment, aluminium foil can be placed around or near those parts at Fig 7. The 7660 in conjunction with cmos ic regulators types 7663 and 7664 can provide a stable 5V positive-and-negative supply from a single 9V battery and danger from contact with the soldering iron. will continue to function even when battery voltage falls below 6V

Tips and topics Amateur Radio Techniques W. G. Borland, G3NXM, has found a very simple way to provide an (7th edn) expanded-scale voltmeter that he has not seen mentioned before, although Pat Hawker, G3VA he feels it must have been thought of before now. He writes: "Having built Basically an ideas and source book, this ever-popular work brings together a a 13.5V power supply I wished to monitor the output voltage. A I5V fsd large selection of novel circuits arid devices, together with many fault- meter would have given too cramped a scale, and I was interested only in finding and constructional hints. the range from about 12 to 15V. A 60kil resistor in series with a 50pA fsd Chapter titles: Semiconductors; Components and construction; Receiver topics; Oscillator topics;, Transmitter topics; Audio and modulation; Power meter gave me a 0-3V meter. This I connected in series with a I2V zener supplies; Aleflid topics; Fault-finding and test units. diode. I now had a voltmeter which reads 12-15V! Owing to the tolerance "An alternative title for this book would be The Experimenter's Hand- in zener diodes (mine was II. 8V) it helps if the series resistor is made up of book. It is one of the finest collections of circuits, building blocks, and fixed plus variable components that provide a value variable to rather design ideas, and is invaluable for the inveterate amateur experimenter and constructor"— Amateur Radio (Wireless Institute of Australia). above 60k1l." 368 pages; paperback; 246 by 184mm; 1960 To provide overcurrent protection for I2V equipment (car electronics), Daniel Appiolaza (Electronics, "Designer's casebook", 24 February 1981,

RADIO COMMUNICATION June 1981 535 O.845 __.1 15m m 0./d copper water-pipe 4 BA screw fixing reflector disc 1.59" long x Vewlde slot MICRO WAVES to Inner (2nd slot located on opposite side)

1.69" Charles Suckling, G3WDG* . dia

V edia copper or First transatlantic 2-3GHz (ISO brass rod

During April, PAOSSB (assisted by PAODBQ) and W6YFK succeeded in 1/1etrifek S solder making what is believed to be the first transatlantic QS0 on 2.3GHz. The SP ptfe spacer equipment at W6YFK-18ft (5.5m) dish, 700W output from a klystron amplifier, and IdB nf gasfet preamp—had been ready for a QS° for a 1.69' number of years, bin until recently there was no other station equipped for eme. PAOSSB and PAODBQ have been working towards tests with Rg 1. The dipole reflector dish feed for 3.40Hz W6YFK over the past year, and this contact was the culmination of much hard work. Their equipment consisted of a 20ft (6. I m) dish, 100W output must allow for some inward and outward adjustment of the position of the from a homebuilt transmitter, and a 4dB nf receiver. Congratulations feed for optimum gain. The feed should first be located so that the focus indeed to all involved in this remarkable QS°. of the dish is midway between the dipole and the reflector, and once set up, it should be locked firmly in position. A dipole-reflector dish feed for 3-4GHz G3ZEZ reports very good results with this feed used in a 0-41 f/d dish. Dish feeds for the lower microwave bands may conveniently take the form of either circular waveguide horns or disc/dipole combinations. A version A double-slug tuner for 1.3GHz of the latter type has been developed by G3ZEZ for 3 • 4GHz, and is shown Very frequently 2C39 type amplifiers for I 3GHz produce rather less rf in Fig I. The mechanical arrangement used to hold the feed in the dish output than expected. Apart from being detrimental to overall equipment performance, the low efficiency (ie less than about 50 per cent) of such a pa stage can have other undesirable consequences, especially when valves arc being run close to (or beyond!) their rated limits. In particular, low effi- ciency can cause internal overheating of the valve, resulting in, at best, ex- cessive tuning drift, and, at worst, permanent damage to the valves. Low efficiency can arise from a number of causes, such as poor valves, a badly designed or constructed cavity, and incorrect operating/tuning conditions. One very common cause of low efficiency is incorrect loading. Many amplifier designs do have some sort of adjustable output coupling, such as a rotatable loop, while others do not (cg the WB6I0M twin 2C39 amplifier). The output circuitry evolved for such designs may well have been suitable for the, original running conditions (ie anode voltage, anode current, drive level, valve type etc) but will not be optimum in all cases. Also, such circuits can be rather difficult to tune up for optimum perfor- , The 8m dish belong• ing to OZ9CR, used mance. for 1.3GHz eme One solution to the problem of incorrect loading is to use an external impedance matching device (tuner) between the amplifier and the antenna. This can be adjusted empirically during tuning up, in conjunction with the existing loading control if necessary, to produce optimum loading and thus maximum rf output. Various types of tuner can be used for this, but the preferred type on grounds of ease of construction and lowest loss is the double-slug tuner. In this type, two dielectric slugs (usually made from ptfe) each A/4 long (tak- ing account of the velocity factor) are moved independently inside a coax- ial line to perform the impedance matching. The range of vswr which can be matched is up to 4:1, using ptfe slugs. A design for a I • 3GHz double-slug tuner is shown in Fig 2, and is an adaptation of the original W2IMU version. It can be used at other fre- quencies by simply scaling the lengths of the slugs and of the complete tuner inversely with frequency (ie for 2.3GHz the slugs would be 22.9mm long). The diameter of the inner conductor should be such as to give the desired characteristic impedance. For 5012, using 15mm o/d waterpipe as the outer conductor, 6mm diameter rod is the near optimum: 0-25in 46 Windsor Close, Towcester, Northants, (6.3mm) can be used, but the resulting 45I2 characteristic impedance will

311 5m m 295 m m r 4m m 14m m • S. solder

4 `,1,t6t.rrm,i 40 6m m -iii 2min wide slot ptfe _r Ç=P2222?22: =2q

r- 30.taper

2.28 mm dia \ Open out hole In nut to 15m m di* fora depth of 2m m 15m m WcI x 13.51m m Yd copper water -pipe See text

Fig 2. Double-slug tuner for 1.3GHz

536 RADIO COMMUNICATION June 1981 reduce (slightly) the range of adjustment of the tuner. Alternatively, a 5011 line can be made from 0. I87in (4.7mm) diameter rod and 0.437in (II , Imm) i/d tube. The construction of the tuner is straightforward, the most important point being to select an undamaged piece of tubing for an outer conductor. The ptfe slugs should be machined to be a sliding fit with both the inner and outer, and any dents in the outer will prevent easy adjustment of the slug positions. The slot in the outer conductor can be made either by mill- ing or by drilling a large number of holes next to each other and then filing out. In either case, the tube may tend to open out due to residual manufac- turing stresses, and it will be necessary to restore its shape. This can be done by squeezing the tube (carefully!) to shape in a vice and soldering a small tab across the slot halfway along the tuner. The RSGB stand at the convention was manned by a happy band of helpers The lengths of the inner and outer conductors shown arc correct for the and RSGB staff. Photo: G3SZJ NJ-connectors quoted. If different types are used it may be necessary to change the length of the inner conductor slightly, or the centre pins of the connector may not be in the correct positions. demonstrated for aligning antennas, and the calculation of beam headings In use, this tuner has been essential in obtaining good performance from using national grid references was described. At the end of their lecture, a UPX-4 type six-valve amplifier. The insertion loss of the tuner has been G4CNV and G4KGC gave a live demonstration of a lOGHz link. measured as less than 0•05dB, and it will safely handle 500W. In the second lecture, G3WDG outlined the advantages to be gained in Measurements with a Narda "yellow ball" type rf radiation detector have using microwaves for moonbounce. Because of the higher gain of anten- shown no significant leakage of rf from the slot. Of course, care should be nas in the microwave range it turned out that I • 3GHz and 2•3GHz were taken during adjustment of the slugs not to touch the inner conductor with more promising for "back-garden" eme than 144 or 432MHz. The higher any metal object while it is carrying rf. bands were less promising because of difficulties in generating sufficient Apart from being used in conjuction with power amplifiers, the tuner transmit power. He described typical eme equipment for l • 3 and 2.3GHz can be used for tuning out any small antenna or changeover relay vswrs, and how this was integrated to form a complete station. It was suggested which may be of advantage when vswr-sensitive, low-noise preamps are that 1-3GHz is perhaps the easiest microwave band for eme. The re- used. quirements for eme antennas were discussed and the reason why circular polarization is used were outlined. RSGB National VHF Convention 1981 The third lecture, on microwave propagation, was given by Barry The new venue of the convention at Sandown Park was certainly of benefit Chambers, G8AGN. He continued the subject of line-of-sight propagation to the microwave lecture stream, with excellent lecture facilities and large started by G4KGC, and showed that signal levels could be very variable audiences. The first speakers, Hugh Griffiths. G4CNV, and Petra Suckl- when operating over paths which were only just line-of-sight. He then ing, G4KGC, described, respectively, simple equipment for lOGHz and discussed the relevance of atmospheric and tropospheric meteorological the fundamentals of microwave operating. G4CNV described the basic conditions to microwave propagation, and gave a most interesting account waveguide components, and how these arc put together to form a station. of how ducts of various types are found and how they performed as The design and construction of the simplest lOGHz transceiver (a Gunn natural "waveguides" to microwave signals. Tropospheric scatter as a oscillator and in-line mixer) were described in some detail. He then method of working reliable dx on microwaves was also discussed, as was discussed the relative merits of various types of antenna and concluded the effect of rain as a source of enhanced scatter conditions. that horns were by far the simplest for the beginner to make. G4KGC con- The new venue also gave an opportunity to reinstitute the Microwave tinued the lecture by outlining what types of path could be covered with Constructors Competition (for the John Rouse Memorial Trophy). A this simple equipment. The requirement was for line-of-sight, and she number of interesting entries were received, including two very-well- described how to plot paths to check this, taking into account the cur- engineered wideband fm transceivers for lOGHz using the Practical vature of the earth. She then described how to prepare for portable opera- Wireless design and PW cum om-rnade dishes. The winner, declared during tion, how microwave contacts are arranged using 144MHz talkback, and the evening social session, was Clive Elliott, G8ADP, for his homebuilt how to set up equipment on site. The sighting compass method was ''- 5.7GHz narrow-band transmitter/receiver unit.

The presentation during the convention of vhf trophies by RSGB President Basil O'Brien, G2A MV

Top: (1) the Surrey Trophy to the Mardesham RS and Ipswich RC—the Martlesham RS also received the VHF Contests Com mittee Cup: (r) the Scottish VHF Shield to the South of Scotland VHF/UHF Contest Group - this group also received the VHF Manager's Trophy.

Bottom: the HADRABS Contest Group receives the 1951 Council Cup. Photos G4FAW

RADIO COMMUNICATION June 1981 537 Despite these teething troubles the convention was altogether a great success, with most of the credit going to Geoff Stone, G3FZL, the conven- tion organizer, and Eric Yeomanson, G311R, the trade exhibition 4-2-70 }Ili organizer. Thanks are also due to members of the Echelford ARS, who ex- pertly organized the talk-in stations and popular bring-and-buy stand. Preliminary plans are already being formulated for the 1982 RSGB National VHF Convention, which will include a much enlarged trade show, so make a note in your diaries for 13 March 1982, which has been provisionally booked at Sandown Park. John Morris, G4ANB* 1' Aurora There were several minor auroral openings on 144M Hz around the middle of March. GM4IHJ, in Fife, heard GB3GI and 0Y5NS at 1640gmt on 13 RSGB National VHF Convention 1981 March and then worked GM4BYF (YP square) and GM311J. On the A record number of visitors attended the 1981 RSGB National VHF Con- following day there was a weak Scottish-type aurora between 1245 and vention, which took place on 11 April at a fresh venue, the magnificent 1530gmt which produced a contact with GM8MBP (YR square). The sky new grandstand at Sandown Park Racecourse in Surrey. Well over 1,000 was clear but GM4IHJ could see no visual aurora, then, much to his vhf enthusiasts attended the daytime exhibition and lecture sessions, with disgust, American friends reported that they saw a superb visual display more than 100 staying on for the evening supper and entertainment. later that night, The convention address was given by RSGB President Basil O'Brien, The period 8-13 April was dominated by widespread aurora and G2AMV, who welcomed visitors to the convention and gave a brief but massive hf-band blackouts. The Meudon "A" index was at storm levels of lively review of several topics, including citizens band, novice licences, 34, 70 and 72 on It, 12 and 13 April, and on the last day the "A" index at 50MHz, and the hazards of eating soup while wearing the presidential Boulder reached 105, the highest level since April 1979. The visual display chain. Large audiences were attracted to all the lectures, which were given accompanying this storm gave a 2,000-mile-long arc which was seen as far in the spacious and comfortable accommodation at the top of the grands- south as California and Louisiana, and also in New Zealand, a very rare tand. event. Ron Broadbent, G3AAJ, who spends much of his time enthusiastically Considering the level of "A" index the European radio aurora was very promoting the use of amateur satellites, led a team of AMSAT-UK disappointing, with only moderate dx on 144MHz being reported. For members in a session entitled "The new series of Oscars—information and G8LFB (ZL300 the best contacts on 13 April were GM8MBP (YR60e) at explanation". Brian Bower, G3C0J, reviewed the development of 0100gmt and DG2LK (EN19b) at 0353gmt. amateur use and understanding of ionospheric propagation at vhf, with GM4IHJ has noted that at the end of an auroral event, particularly one emphasis on 50MHz. The ever-enthusiastic Charlie Newton, G2FKZ, who of the Scottish type, there is often a brief period when stations far to the puts a great deal of effort into the arduous task of collating and studying south of the auroral horizon are audible with clear T9 or, at worst, T7 auroral reports, gave a talk on "Aurora—the boundary fence problem". signals. A typical incident occurred during the dying minutes of the event Mike Dennison, G3XDV, covered a lot of material in "Repeaters—where on 13 March. At 1717gmt the aurora began to fade, and then at 1720gmt do we go from here?", including a review of the many new types of GM4IHJ was called by G6NB, in Buckinghamshire, whose signals were T9 repeater which could be appearing on the bands in years to come, and he at a beam heading of 25°, but only T7 and slightly weaker with the anten- reiterated the message that the present vhf/uhf fm repeater networks are na pointing along the direct path at 165°. specifically designed and licensed for mobile use. This was not the first incidence of southern signals at the end of an John Nelson, G4FRX, is uniquely qualified to talk on the "Use and aurora, and the phenomenon may well have been noted by others. abuse of transmitting tubes of the 4CX-250 series", and an hour gave him GM4IHJ thought at first that it was caused by the coincidence of an scarcely enough time to do justice to the subject. Among the points made aurora and a little tropospheric bending, but now believes that it occurs were the importance of using the right bases and good power supplies, the too often for this simple explanation to suffice. Other operators may care fallacy of tuning for maximum output, and, in one of the more memorable to listen for this effect to help decide if it is real or imaginary, and, if real, quotes from the convention: "If your blower isn't noisy, it's too small". to establish the propagation mechanism. G4ANB attempted to review the subject of locator systems, including some of the developments during the final few weeks before the Brighton 432MHz IARU Conference. A questionnaire distributed at the end of the lecture in- A letter from Paul Higginson, G8IZR, prompts a reminder of the 432MHz dicated that more than two-thirds of those present favoured changing to activity periods which run from 2130gmt every Monday evening. Although the system described in the November 1980 issue of Rad Coin. the IARU-recommended ssb calling frequency is 432.3MHz, most UK The large exhibition hall at Sandown Park proved to be ideal, and there operators still stick to 432.2MHz, and a call on this frequency during a was little of the overcrowding which occurred in previous years. Demand Monday evening will often bring a reply from one of the many 432MHz for space was so great that the hall was completely booked only seven days enthusiasts who support the activity periods. G8IZR is one of several after the trade notice had been sent out, and many potential exhibitors had amateurs in the Bolton area who have been disappointed by the level of to be reluctantly turned down. The RSGB bookstall saw a brisk trade, and 432MHz activity recently. They are keen to try skeds at almost any time, the displays mounted by BATC, BARTG and AMSAT-UK attracted a including th, local, and tests over difficult paths. Interested operators great deal of interest, and, one hopes, a few new recruits to their specialist should contact G81ZR, QTHR. communication modes. The trade stands had just about everything for the Peter Burden, G3UBX, is a keen 432MHz dxer, but recently his activity vhf enthusiast, from morse keys to moonbeams, and for those more has been curtailed by working away from home. In a letter to 4-2-70 he interested in looking than buying there was plenty of literature commented: "In spite of operation being confined to the odd contest available—your scribe came away with a handful of price lists and data weekend, and having missed the opening at the beginning of February, I sheets, and a calendar of racing fixtures. was pleasantly surprised to note that this year 51 counties and nine coun- Two rooms were used for the social evening, with the Second Founda- tries have been worked, including GMs in XP and YQ squares and a GI in tion Modern Band, including Bob "Boogie" Burns, G300U, providing WP square. Non-weekend operation is confined to 432MHz repeaters and the music for dancing in one, and a separate bar area set aside for conver- fm simplex—some very enjoyable QS0s have been had and the level of sation. A buffet supper was served, and the President presented many activity is surprising." trophies to the winners of vhf/uhf contests. As with any new venue there were a few problems, including the pro- grammes and entrance tickets being left at RSGB HQ, which called for 432MHz eme some rapid improvisation on the gate. Real ale fanatics were disappointed Stuart Jones, GW3XYW, has written to 4-2-70 with a review of his to find only the bottled variety on sale, and there was near panic at lunch- 432MHz moonbounce activities during the end of 1980 and the first few time when even this ran out—fortunately emergency supplies were located months of this year. It is much more difficult to make moonbounce con- and brought in. The standard of catering was generally disappointing, and tacts using ssb than it is with cw, so GW3XYW was understandably this is clearly an area which will have to be investigated before next year. delighted to make his first ssb contact via the moon on 18 December, when DL9KR was worked. Phone was used again on the following day to work I5MSH, giving GW3XYW the second of the two ssb eme contacts he has *24 Collett Way. Grove, wantage, Oxon OXI2 ONT. achieved so far. Conditions were good for the whole of that weekend, with

538 RADIO COMMUNICATION June 1981 the moon close to perigee (the point of closest approach to the earth), and UK 145MHz REPEATER NET WORK, APRIL 1981 at 2100gmt on 19 December GW3XYW completed a cw sked with YV5ZZ Callsign Channel Location Locator Contact for what is thought to be the first OW to YV contact on 432MHz. GB3AR R4 Arfon, Caenarfon, Gwynedd XN79e GW3MZY The new year started fairly quietly, with just three stations, K4QIF, GB3AS R I Caldbeck, Cumbria Y015e G3WJH XP48f GM3KMG G3YGF and W7GBI, being worked during the night of 16-17 January. GB3AY R2 15km south-east Ayr GB3BC 116 8km nnw Newport, Gwent YL35a G4GTD The February activity weekend was similar, yielding contacts with GB3BM R5 Birmingham YM50a G8AMD DL7YCA and VE4MA during the evening of St Valentine's Day. There GB3BP R6 5km east Crawley, W Sussex ZL79f G4EFO was rather more activity during the following month, and the GW3XY W GB3131-* 112 Berwick-upon-Tweed YPlOg G3HDT Leicester ZM24j G8CAC log shows contacts with ZE5JJ and W6ABN on 13 March; SM3AKW, GB3CF RO GB3CS R6 Blackhill, Motherwell YP1 la GM3KMG G3LTF and KAOY on 14 March; and HB9BPQ on 16 March—the last pro- GB3DA R5 Danbury, Essex AL23b G8NMP bably being the first OW to HB contact on 432MHz eme. GW3XYW was GB3EL RO East London AL3lb G4GPQ Burntisland, Fife YQ66h GM3KMG particularly pleased to make his first contact, after several attempts, with GB3FF 114 GB3FR R7 Old Bolingbroke, Lincs AN61g G3NNQ G3LTF, who over the years has been unstinting with help and advice GB3GN R7 Aberdeen YR79f GM4BYT towards reaching moonbounce capability. GB3HH 114 Buxton, Derbyshire ZN6la G3RKL Julian Gannaway, G3YGF, has also been active on 432MHz eme, using GB3HI R4 Isle of Mull X(142g GM3RFA Little Weighton, Humberside ZN 18g G3KOC the 20ft dish at Oxford. He recently worked YV5ZZ for his first contact G133HS 112 GB3KN 114 Maidstone, Kent AL54e G3X0V with South America, continent number five. On the following day GB3KS R I Dover, Kent AL67d G3XDV VK5MC was worked, giving G3YGF his sixth continent and WAC by GB3LD• 113 Ulverston, Lake District G3TZM WP76a G13GGY 432MHz moonbounce. GB3LY RO Limavady, Co Londonderry GB3MH R3 Malvern Hills, Worcs YM79a G3MT1 Browsing through past issues of Rad Coin, it is interesting to note how GB3MN 112 Stockport, Cheshire YN60c G3LEQ the growing popularity of moonbounce has produced more and more GB3MP 116 Moel-Y-Parc, Clwyd YN64a G3LEQ "random" contacts—je those made without prior arrangement. Never- GB3NA -1- R3 Barnsley, Yorkshire ZN33a G8PLJ Tacolneston, Norfolk AM364 G4EOL theless skeds still playa very important role in this experimental work, and GB3NB R 1 GB3NC R5 St Austell, Cornwall XK56b G3XC GW3XYW has expressed his thanks to VE7BBG, who for many years has GB3N1 R5 Belfast X032h GI3TLT been responsible for setting up skeds for eme operators worldwide. This GB3NL 117 North London ZL30e G8IUC AM7lf G8MEI task has now been taken over by G3WDG. GB3PI 116 Barkway, Herts GB3P0 R3 Martlesham Heath, Suffolk AM77j G3ZNU GB3PR R3 Perth YQ53b GM8KPH EME data transmission experiments GB3RF R7 Burnley, Lancs YN19e G3RXH GB3SB• RO Jedburgh, Borders YP34f GM4E2J J. P. Martinez, G3PLX, of Amtor fame, recently joined the Oxford EME GB3SC R1 Wimborne, Dorset YK30c G3VPC Group for a further series of tests on the feasibility of using data transmis- GB3S1 R I St Ives, Cornwall XK63j G3NPB South London ZL50j G3PAO sion techniques on moonbounce. Two experiments were carried out on GB3SL 112 GB3SN R5 Fourrnarks, Hants ZL57b GBCKN 432MHz using the Oxford 20ft dish with computer programs developed by GB3SR 113 Brighton, Sussex ZK201 G4EFO G3PLX. In the first a code sequence was transmitted and the echo from GB3SS* RO 16km south-east Elgin YR25g GM41A0 the moon received and compared by software with the original transmis- GB3TR 112 Torquay, Devon YK32d G4FCN Tyne Et Wear 2012j G4DOB sion. In this way the time taken for the signal to travel from the earth to GB3TW-I- R5 GB3VTt R1 Stoke-on-Trent YN80e G3LECt the moon and back was measured, so allowing the distance to the moon to GB3WH 114 Abingdon, Oxon ZL24d G4DPA be çalculated, the whole set-up effectively acting as a radar range finder. GB3WLt R I West London ZL3Bd G3PAQ YL67b G3CCIE In the second series of experiments 2.5s bursts of pseudo random data GB3WR RO Wells, Somerset GB3WT R7 West Tyrone W033b GI3XCZ were sent using afsk at 100bps. The very weak return signals were then GB3VVW 117 Carmel, Dyfed XL30a GW3VPL decoded and compared with the transmitted data to give an indication of GB3YJ• R7 Leamington Spa ZM53e G8IXE the error rate which could be expected when using moonbounce for data communication. The preliminary results of these tests were extremely en- *Licensed, not yet operational j-Temporarily off the air couraging and suggested that it should be possible to get completely error- free communication via the moon at several letters per second. This is much better than can be achieved using cw, even by a very experienced operator, so this technique looks very interesting indecd. G3PLX is 18 months GW4HBZ has made over 80 crossband contacts, including all analysing recordings of the echoes, and hopes to be able to deduce an op- of the USA call areas. On 25 November 1979 at 1255gmt W4UWH/KV4 timum code for eme data transmission. Full results will be reported at a was worked, predating by one week the contact between GW3AHN and later date when the experiments have been fully evaluated. W4VWH/KV4 reported in April's 4-2-70. G4BPY made crossband contacts with several South African stations Repeater news during the second half of March. At 1251gmt on 26 March the ZS1STB The Home Office has licensed another of the 433MHz repeaters in uhf 50MHz beacon located near the southern tip of Africa was logged. This Phase 5, GB3VH (RBI3, Hatfield, Herts). This leaves GB3HZ (RB4, was the first recorded observation of ZSISTB in northern Europe. On 28 Hazlemere, Bucks) as the only outstanding proposal in this phase. March G4BPY heard the 50.08MHz Durban beacon ZS5VHF, and at Preparation of uhf Phase 6 for submission to the Home Office is near- I304gmt completed a crossband contact with ZS2SS in Port Elizabeth for ing completion, with two more units having been added to the list publish- a possible G-ZS2 28-50MHz "first". Reception reports for ZS5VHF ed in last month's 4-2-70; GB3HD in Huddersfield and GB3WP in east would be welcomed by ZS5TR, and for ZS1STB by ZS6PW. Manchester. Channels for these proposals have not yet been decided. Throughout the summer a 50MHz discussion net will meet on Saturdays Unfamiliar handwriting allowed a slight error to creep into the publish- at 1900gmt on 28.885, 21.400 or 14. 345MHz, depending on propagation ed list. The proposed callsign for a uhf repeater in Peterhead is to be conditions. Further information is available from S. Richardson, G4.1CC, GB3PD. on 070 163504. GB3AY (R2, 15km south-east of Ayr) was due to become operational on 25 April. GB3PB (RBIO, Peterborough) was taken off the air on 3 Expeditions April and re-engineered with a microprocessor control system and new The expedition season is well and truly here again, and even the ever- transmitter and receiver. Coverage should be slightly improved, and escalating expense of transporting equipment and running generators reports would be welcomed by G8OUU. GB3PH (RB2, Portsdown Hill. cannot deter more and more groups every year from participating in this Hampshire) was closed down for a few days at the end of March for traditional summer activity. modifications to the logic circuitry. GB3NX (RI32, Crawley, Sussex) was GW6AJK, GM8OFV and G8K WX recently visited the Mull of due to be off the air during most of April for routine maintenance. Galloway in south-west Scot land to look for a suitable site for the Univer- sity of Liverpool ARS expedition. The location selected is 6km south-west 50MHz of Glen luce, in locator X018h. The expedition will run from 10 to 20 July. Brian Clowes, GW4HBZ, has been active on 50-28MHz crossband since The club callsigns GM3OUL/P and GM8JUL/P, and possibly an addi- November 1979. His attention was first drawn to the band by G8BMJ. The tional special event callsign, will be used. There should be no shortage of equipment used for crossband operation consists of an FT101 driving a operators as at least nine licensed members of UoLARS will be making the two-element beam on 28MHz, with a home-built two-element beam and trip, and they hope to be active on all bands up to I,296MHz. Several mosfet converter feeding an FT225R for 50MHz receive. During the past groups have visited the Mull of Galloway during recent years, and all have

RADIO COMMUNICATION June 1981 539 put out good signals and been very popular on the bands. This latest ex- while uhf Ch 8525 is 438.525MHz. VHF channels 6625-7000 and pedition looks like being no exception and it should provide a fine oppor- 7025-7375 are used for repeater outputs, the inputs being 600kHz lower tunity to work this comparatively rare part of the country. for the first group and 600kHz higher for the second. Among the 63 vhf After returning from their scouting trip to Scotland, G8KWX, repeaters are three devoted to rtty and one to sstv. Both 1.6 and 5MHz GM801.1/ and GW6AJK operated G8JUL/P on 144MHz from the sum- offsets are used by Australian uhf repeaters, of which nine are opera- mit of Helvellyn in the Lake District on I April, and they wish to thank all tional. of the stations who called them. GW6AJK is sure that many operators, on GU2FRO recently returned from an enjoyable trip to New Zealand, hearing "CQ two from the summit of Helvellyn" on April Fools' Day during which he used an 1C2A handheld rig to operate both simplex and must have thought it all a joke. Equipment comprised an IC260E, 40W via repeaters. He advises those planning a similar trip to take along their amplifier and eight-element Yagi. Power came from a very heavy car bat- RAE certificate, morse test pass slip where appropriate and UK licence tery, which required quite a lot of effort to get it to the top of the moun- when applying for a reciprocal licence. tain. Stations as far away as Dorset were worked, but lack of time, cold winds and cloud prevented a longer stay on the 3,1 161t asl summit. Those Scatter who still think it was a joke may be assured that QSL cards are on their Many amateurs have had trouble with interference, but two recently- way. reported incidents indicate the scale of the problem is not always fully ap- Derek and Valerie Fellow, G4IGZ and 08 VAL, are planning a vhf/uhf predated. The first involved G3VZV, who found himself on the receiving trip to France, where they will be known as FOEUR and FOFSD, and An- end of tvi while watching the BBC on Band I. The miscreant turned out to dorra, where they will use the callsigns C3ISY and C31V1 respectively. be VEIASJ on 50MHz. The second was caused by the I44MHz operation The first period of operation will be from the French part of BC locator of G4DEZ, one of whose neighbours complained of an intermittent square between 26 July and 9 August. From 10 to 14 August, and possibly strange noise coming from his electric heater. during the contest on 2 August, operation will be from Andorra, in AC G4JKN, in Barnstaple, and G3ZIG, in Norfolk, have a contact on locator square. The operating frequencies from both locations will be I44MHz each morning by aircraft scatter. Path loss calculations imply the 144.35 and 432-35MHz. During a trip to Andorra in July 1980 G4IGZ flight path of the aeroplane responsible passes close to one or other of the observed a 20min opening when the G'B3VHF beacon was audible, but no stations, probably G4JKN. Each contact lasts for about 5min, starting at other stations could be heard on the band. A few days later came the spec- 7.35am. Does any aviation expert know of a regular flight which passes tacular lift when C3INT worked just about everybody in the south of over north Devon at about this time each morning? England. This year G4IGZ is "taking along the Nag (linear)". G8VMF has received a report of his callsign being pirated by a station in News has been received that G8IBP and G6ADF will be operational on the London area. The genuine G8VMF lives many miles from the I44MHz from County Wicklow in the Republic of Ireland from 12 to 27 metropolis. June. Details of the callsigns to be used are not known at the time of In response to popular demand, deadlines for contributions to 4-2-70 writing. will be published for an experimental trial period, and a few words by way of explanation of these deadlines are in order. 4-2-70 is composed over a weekend, so all vhf/uhf news and views must be with your scribe by the AGC W-DL vhf/uhf cw contests morning of the appropriate Saturday at the latest. There are a few days Every year the German cw activity group AGCW-DL sponsors three following the deadline during which a small amount of "stop-press" type vhf/uhf cw contests, and over recent years several UK amateurs have news can be accommodated, but beware!—anything of less than earth- entered these short Saturday evening events. Each contest runs from 1900 shattering import which arrives during this period is perforce liable to be to 230C1gmt, and the next three are: held over until the following month. 27 June, 144-01 to I44• I5MHz; All material for August to reach G4ANB by Saturday 13 June (late news 26 September, 144-01 to 144. I5MHz; and by 23 June) and for September by Saturday I I July (late news by 21 July) 20 March 1982, 432.00 to 432. I 5MHz. please. There are three classes, according to output power: A, less than 3-5W; B, less than 25W; and C, more than 25W. The contest exchange is RST plus QS0 number (starting at 001)/class/locator; for example, 579001/B/EL25a. The score for each contact depends on the output class of each station: A to A, 9 points; A-B, 7; A-C, 5; B -B, 4; B-C, 3; and C-C, 2. Contacts with stations who do not give a full contest report count one point each. Each big QTH locator square worked gives one multiplier point, and each DXCC country an extra five. The final score is the sum of contact points times the sum of multiplier points. Only single operator en- tries are allowed, and they should be sent to Edmund Ramm, DK3UZ, PO Box 38, D-2358 Kaltenkirchen, Fed Rep of Germany, postmarked not later than the last day of the month following the contest. Amateur Television Handbook, edited by John Wood, G3YQC, and Trevor Brown, G8CJS. Published by British Amateur Television Club. Antipodean channels 96pp. Available from BATC, or RSGB Publications (Sales) price £2.39 Eric Woolley, GU2FRO, has very kindly provided a copy of the New incl p & p. Zealand call book, which is a veritable mine of fascinating information, including details of the amateur frequency allocations, band plans, and This new handbook is mainly concerned with high-definition, fast-scan tv on the repeater networks in both Australia and New Zealand. 432MHz band. Its aim is to deal with some of the more complex and less-well- The New Zealand vhf/uhf amateur bands are 51-53, 144-148 and publicised techniques used in the modern atv station, and it contains little information on topics which are already adequately covered in other readily-available publica- 420-449.75MHz, the ssb calling frequencies being 51.2, 144• 2 and tions, such as antennas, licensing conditions, and even transmitters. Instead em- 432-2MHz. FM simplex uses 50kHz channel spacing, starting at 52.525, phasis is placed on such subjects as modern receiving systems, electronic video 146.0 and 433.3MHz. The ZL repeater list gives details of nearly 50 units, sources, vision processing techniques and colour tv, although there is a brief in- using channels denoted by single letters. Channels A to G have inputs troductory chapter containing guidance for the newcomer. Most of the book is taken up with practical projects, ranging from the modification spaced at 50kHz intervals from 146.2 to 146.5MHz, the odd man out be- of a broadcast tuner to receive amateur transmissions to a complete digital colour test ing Ch B with an input frequency of 146-225MHz. Unusually, the repeater card generator. Few of the projects have ever been published before, and indeed outputs are 700kHz below the inputs, and a browse through the advertis- some were specially produced for the handbook. An excellent feature of the video cir- cuits is that they have been designed to be mutually compatible and use standard size ing section indicates that the ability to operate with this frequency split is a pc boards, many of which are being made available by BATC. Each circuit is accom- strong selling point for vhf transceivers. Channels Q to V are for uhf fm panied by an explanation of its function and method of operation, as well as notes on repeaters, which have inputs between 433-5 and 433-75MHz, and outputs construction, setting up and use. The text is well written and complemented by 5MHz higher. There arc also five a.m. repeaters in the country, with out- numerous diagrams. It will be a welcome addition to the bookshelf, both for the atv enthusiast and for puts on 145.775 and 145-825MHz, and inputs 1. I 25MHz lower. The wide anybody interested in uhf and video circuit design. uhf allocation means that there is plenty of room for television, and this is BATC also publishes a quarterly magazine of operating news and technical articles. utilized by an in-band atv repeater at Wellington. CO-TV, which is distributed to all members and is required reading for all atv devotees. Membership of BATC costs £3 per year (plus 50p enrolment fee), and Australian fm uses 25kHz channel spacing, and the channel numbers details may be obtained by sending an sae to the membership secretary, Mr B. Sum- consist of the final four digits of the appropriate frequency, expressed in mers. 13 Church St. Gainsborough, Lincs. kilohertz. Thus vhf Ch 6500, the national calling channel, is 146•500MHz, G4ANB

540 RADIO COMMUNICATION June 1981 1981 hf countries table

Station 28 21 14 7 3-5 1.8 Total Mode A8808 166 148 140 105 95 34 688 sercw 8RS14585 157 145 137 100 108 11 648 ssb/cw SWL NEWS 11542604 128 144 121 115 Ill 15 634 ssb 8RS48909 153 159 162 70 50 18 612 ssb 8FIS8841 122 130 174 90 80 5 601 ssbicw BRS10E6 115 115 123 79 59 29 520 ssb/cw BRS44703 101 67 70 78 73 0 389 sab AR 542503 81 87 117 18 27 o 330 ssb 8RS442EG 108 31 83 23 7 10 262 ssb Bob Treacher, RS32525* ] ARS41349 44 73 51 25 34 2 229 ssb 8RS18529 36 18 sa 45 60 10 227 ssb BRS41992 33 22 70 36 46 13 220 ssb BRS35509 43 38 71 36 25 1 214 se TV-DX A9191 56 33 60 26 29 3 207 ssb/cw A national dxtv reception group has been formed under the guidance of George Grzebieniak, RS4I733. It has met several times in the London area All time countries list since February 1981. A number of members have already acquired tv (Starting score 750) equipment, ranging from a Sin multi-band black and white set to a 27in Station 28 21 14 7 3.5 1-8 Total Mode EIRS25429 2E8 301 326 227 220 53 1395 ssb full-colour model that has provision for satellite reception. A considerable G3KMA 298 317 322 241 173 41 1392 ssb/cw wealth of knowledge, experience and practical ability has surfaced from BRS 17567 282 317 350 181 226 34 1390 ssbicw BRS32525 259 293 313 227 242 41 1375 tab the membership to date and this has been pooled. This advice and BRS25901 252 290 321 191 195 22 1271 ssb/cw help, freely given, enables everyone to maximize the pleasures of tv dxing. 8R535943 232 274 297 198 218 30 1249 ssb RS42604 261 2E8 262 223 167 45 1227 ssb Anyone wishing to join the group should write to George, c/o 185 Fleet 03010 293 315 319 139 117 27 1210 ssbrcw Street, London EC4A 2HS, enclosing a sase. A8808 230 264 290 158 163 53 1158 ssb/cw G3MCS 278 293 303 142 118 18 1152 ssb BRS8841 220 252 305 156 163 18 1114 ssbicw DX swl G3AL1 180 206 299 162 184 0 1031 ssbicw G3IG W 169 188 214 187 127 e2 967 ssbrcw Greetings to Stan Porter, RS45992 (ex 9J2-53 I), who wrote from 7Q7. He G4FAM 195 220 225 160 114 31 945 ssinrcw BRS43475 184 229 239 129 107 31 919 ssb/cw provided some interesting data from southern Africa. He uses an FRG7 A9191 174 211 250 94 104 18 851 ssbrcw with two inverted-L antennas and a CR100/2, salvaged from a Royal Navy BRS1066 148 153 240 128 83 37 789 ssb/cw battleship in 1942, and both are powered by generator. He usually listens between 0300-0530 and 1600-2000 daily. He is keen to get in touch with someone like himself-way out in the bush and with no radio enthusiasts is usual when sending a QSL to the USA to include two ircs-this covers for hundreds of miles. His nearest amateur was 912AK, and then he returned to Japan! Stan comments on poor propagation to his part of the an air mail reply. Brad Bradbury, BRS1066, now has 199 countries con- firmed from 259 heard. He mentions the debated legality of 9U5DS and world on 7 and 3 -5MHz. There is much QRM on both bands and it is usual only to find stations from ZE and ZS operating. He is somewhat surpris- says he passed a card through the bureau recently from him. It did not give ed at his, so far, poor QSL return, bearing in mind how "rare" he is. a QTH but said "QSL via bureau" and was signed "Guy, 9U5DL". The mystery deepens! When in G-land Stan's QTH is near Camberley in Surrey, and he hopes some dxer/swl in that area could get in touch with him so that he could Paul Crankshaw, BRS48909, reports a great deal of activity during March and April. New countries for him were K6LPL/CEO, KA I AA visit them on his occasional returns home. For the record Stan-who has (Minami Torishima), ZL3AFH/A and ZL3PA/C, the last three being also been to 9Y4, 9M2, 9M8, 8R I, EL, 5N, TU2, 9V1. VS6 and YBO-can heard on the daily "220" net. He comments that this net is probably better be reached at PO Box I, Mbalachanda, Mzimba, Malawi. than any other for Pacific dx. Paul also mentions good 28M Hz condi- tions- WA ISQB/CEO, JTIAN, VK9NYG (Cocos-Keeling Is), and many Newcomers UAOs between 1100 and 1400. He also lists some useful loggings on Nearer home, welcome to Mike Price, ARS45940, who uses a National 14MHz, the most interesting being LU2XTA at Tierra del Fuego. He Panasonic DR26 into a longwire. Examinations hinder his swl activities at overheard an SV8 in QSO with a GM say that he had heard a ZA6 station present but he was hoping to contact G2DYM concerning his antenna on low-power and apparently genuine. Another mystery? systems, which were mentioned in last December's issue. Robert Small, BRS8841, reports K6LPL/CEOZ for country No 310. He John Sutton, BRS35509, writes from Kent. Although he has been an swl has 306 confirmed, the outstanding four being HKO (Serrana Bank), for six years he has found little time until now for listening on his two XW8GZ, BV2B and the CEOZ. He has received the ADXA (30 Asian HROs and an FRG7700. He submits a score for thd table, having reached countries confirmed) and AJD (all JA call areas confirmed) awards via his the 200 entry mark in only two weeks. friend .1H4MUQ. All the bands had provided Robert with new countries Alistair Young, BRS45I73, has been building up a shack over the past recently and he had a lot of other good dx to offer-time or space prevent few months. He now has a Trio R1000, a converter for 144MHz, an HF5 a long list, but examples are LAI RR/STO, Z.K I XI, VK9CCT, CEODFL vertical for hf reception and 5À/8 vertical for vhf. He was sitting the RAE (Easter Is) and 9H3AM. in May and was hopeful of a first-time pass, as he has already set up some Dave Whitaker, BRS25429 seems to have turned his attention to skcds with some friends in OZ. 144MHz dx for the time being. His QTH is 600ft asl and in mid-April he copied stations from PAO, DL and OZ. Newspot Several more regular reporters have swelled the post bag this time with The tables some excellent reports. Paul Tittensor, A8808, caught up with the J5AG Please continue to submit entries for the 1981 countries table. This year's expedition on all five bands on ssb and cw, but at the time of writing had table is growing slowly and it is clear that it will be tight at the top. In an heard nothing of ADOS/KH5. In WPX at the end of March, Paul bagged attempt to salvage a few more lines of text, your scribe has decided to in- EF6BDX, EA9EU and OHOXX/OJO for three new ones on I-8MHz. He crease the entry score for the all-time table to 750, and those with entries reports useful dx on 7MHz around 2200 -HC, OX, UF6, UH8, VU2, ZD8, must up-date their score at least every six months to retain a place in the ZP5 and 9Y4, although he missed out on TL8RC and TYAI I. Some table. This new "rule" is implemented from this issue, but those who fall urgent attention to 28MHz provided 3B9CF, KP4KK/DU2, VP8ADE from the table-and there arc only a few-should continue to keep their (Adelaide Is), VK9NL, 9M2GZ and FK8CR. The band has also produced records so that they can re-enter at the appropriate time. T3OAT and VR6TC around 1945 at good strength. David Hawes, A919I, is trying to spread his listening time evenly over Rhys Thomas, ARS457 17. reports some interesting contacts heard, in- all the bands during the first part of the year, and then he will concentrate cluding KL7AM, who said that he had founded the JARL before he mov- on each band for a few days later in the year. ed to KL7. His QSL cards apparently fetch $100 on the black market because of his fame! He asked for information about the international Reminders reply coupon. Basically, one ire is exchangeable for a stamp or stamps to Next month may see the publication of Cray Valley RS I I th SWL Contest cover the minimum postage for a letter sent by surface mail to a foreign rules. The dates will be 12 and 13 September. A reminder that the country which is a member of the Universal Postal Union. For example, it W6Q0/K6HHD QSL Manager's List is available from Brian Russell, BRS33915, 163 Halton Road, Runcorn, Cheshire WA7 5RJ, price I:I.

• 79 Granby Road, al um, London SE9 1EH Next month's deadline is Mondas IS June.

RADIO COMMUNICATION June 1981 541 THE MONTH ON THE AIR

1John Allaway, G3FKM* ---

"—But he didn't QSL!" The wicked dx station is always the villain but how often is it the fault of the station who so badly needs the confirmation? The latest of a number of low-key operations from overseas locations by G3AAE was in October 1980, when G3AAE/VP9 was QRV for two-and- half weeks, and you would be amazed at the spread of errors on QSL cards which have been received in only four months. Bear in mind that a dx station can easily fill a page ola log book in under ¿O min. and that it takes longer to G3GIQ is chasing a DXCC in visitors, and is now contemplating stickers! One find the entry in the log and fill in the QSL card (even when the details are of his recent guests, seen here, was Ann, F6CYL 100 per cent accurate) than it does to have the QS°, so you can imagine what happens when errors are made. VK9NYG may be found almost daily from 1100 to 1200 near Here are some of the errors to date on QSLs received for G3AAE/VP9 contacts: 28,430kHz, and from 1300 to 1500 between 28,500 and 28,600kHz. (1) Incorrect time—even an hour wrong can be difficult to find. Sometimes he QSYs to the area between 21,150 and 21,200kHz. QSLs (2) Incorrect date—particularly common when the QSO was near to should be sent via VK6NE. midnight gmt. According to QRZ DX, Brian, ZL2BGD, is on Niue Is and will be there (3) No QSO. Very easy in a pile-up when two similar callsigns are involved for two years. He is responsible for the island's communication network but the dx station has one QSO and callsign in his log. and expects to be on all bands 3.5 to 28MHz. His callsign is ZK2BGD and (4) Incorrect callsign. So far cards have been received for G3AAE/VP9 con- he says that there may well be more ZK2s as a radio club is being formed. tacts addressed to G3AAE, G3AA/VP9, G3AAE/VP2, G3AAE/VP8, ZKICG. who is also KA7HRK, is now active on all bands 3-5 to G3AAE/IP9 and G3AAI/VP9, and no doubt there are others more way out that have gone astray. 28MHz, and another unusual Pacific area station, VK9ZD, on Willis Is, is Last October nearly 2,000 QS0s with 163 countries were made from reported to be often around 14,220kHz on Saturday mornings. Bermuda, and all incoming cards are given "same day" treatment. Another DX News Sheet says that the new Postmaster-General of Malawi was period of G3AAE/VP9 operation will take place between 15 October and 5 formerly 7P8AY and that he is hoping to have a 7Q7 call in due course. November 1981. These arc not dxpeditions and the contacts made are From the French islands in the southern Indian Ocean, FB8YI has been relatively few—so the problem must be aggravated many times when worked in the "French area" of I4MHz ssb in the early morning, and someone fires-up from Heard Island or Kingman Reef! FB8XM has been logged just below 14,200kHz in the evening. Confucius he say "Accuracy is rewarded by maximum confirmation!" The Zero District Net meets on 28,597kHz at between 1530 and 1630 on (Thanks to John Kay, G3AAE,t Tuesdays and Wednesdays. Its purpose is to help those looking for WO states for WAS. Surrounding states such as Wyoming, Montana and Utah Roger Napper, G4FXU, wishes readers to know that his callsign is being also join in from time to time. pirated. This seems to have been taking place since 1979, and QSLs are ar- QSLs for contacts with 600DX made since 28 July 1980 arc now being riving for contacts with dx stations—some of whom thank him for his card accepted for DXCC credit. At the time of writing no decision on the re- already received. . . . quest for IAOKM to be counted as a separate country from Italy had been announced. -Bob Lyon, K4FXP, is anxious to trace a source of confirmation for a contact which he had with G3PE/VS9K in October 1961. Anyone able to 5A9BQ has been active on 2IMHz ssb and claiming to be a station help is invited ro contact G3FKM. owned by three Italian engineers in a town 100km southwest of Tripoli. Peter Raven, G4KLM (formerly G8.1ZU), reports the receipt of QSLs They claim to have permission to be on the air and ask for QSLs to Box 73, for alleged cw QS0s on the hf bands. The operator's name is given as Yefreen, Libya. "Len". Peter is not active on cw but uses rtty on 14, 21 and 28MHz. Two special event stations have been on the air recently. W3USS was located in the US Senate building in Washington. A special certificate will be sent to those who work the station if they send three ircs to the address DX news in "QTH Corner". RG4G commemorated Yuri Gagarin and was located During the last week of this month the Taranto section of ARI will be ac- at the site where he landed from space in 1961. QSLs should be sent via tivating Cheradi Is in the Ionian Sea—a special prefix, IJ7, will be in use. UK4CAA. The island counts for the IOTA Award. The actual position concerning the G3JKI/5A operation has been clarified by Arthur himself via G4E0W. It seems that G3JKI has been News from overseas working in Libya for the Libyan Government and that he has submitted Tony Glaser, G3ZEN, is at present in Montserrat and on the air as letters from the Libyan Army confirming his operation to ARRL. These VP2MIX. In a letter to G3FKM he makes some observations on life at the were not accepted, so photocopies of his passport and visa were also for- other end of the pile-ups. He feels that a beam is essential when using ssb warded early in April. F6CYL was expected to begin sending out QSLs at as otherwise one's signal becomes swamped by the loud signals from the the end of the month—whether DXCC status had been accepted or not. USA, and he suspects that many of the "big boys" generate so much Some 5,000 QS0s were made during the operation and a further visit is ex- QRM that they cannot hear the dx they wish to work. On the other hand pected to take place. cw operation is easy, with frequent pile-ups mostly consisting of moderate- VP8AGX, Steve, is a new operator on the air from Adelaide Is, and he ly disciplined Europeans and totally orderly JAs. He thinks that UK sta- is often to be found on I4,267kHz on Monday evenings from about 1900. tions tend to make longer calls than some others, and advises that short QSLs should be sent via G4JDT. Other current VP8 area activity includes calls are much more effective. He feels that certain low-power stations can that by Dennis, VP8ZR, who is located on S Orkney Is. He is often to be cause problems, as a few disobey all good operating standards by calling found near 21,240kHz at 2000. Another rare VP8 area, South Georgia, is continuously and adding the "/QRP" as though it gives them licence to do currently represented by VP8AEN who has been worked on I 4MHz ssb what they will. Tony can usually be found between 2300 and 0300 in the (below 14,200kHz) between 1900 and 2100. VP8SU has now closed down. Our apologies to Angus, ZS lZF, shown operating at his station at Constantio, Cape Town, on page 444 last month, for the loss of the caption during printing. • 10 Knightlow Road, Birmingham B17 8QB

542 RADIO COMMUNICATION June 1981 bottom 25kHz of 7,14 or 2IMHz. Finally he advises amateurs visiting the Top Band West Indies to take a hand-held 144MHz transceiver, as 146.52MHz is G3RPB has answered your scribe's request for more information of generally well monitored and there are quite a few repeaters. 1.8MHz "firsts" by sending details of QSLs in his collection which are en- ZD7SD, ZD7SS and G3JMH have now completed 400 QS0s—mostly dorsed "First G" QS0 with the country. They are G3RPB-PAOPN on 14 and 2IMHz. Bill and Sybil Stevens have never been off St Helena, (7/12/62), G3RPB-ZP9AY (11/6/70), G3RPB-6W8CW (5/11/67) and and their home is about 800ft as1 with a clear take-off in all directions. G3RPB-ZB2A (22/2/65). In addition to these he suggests that the Their equipment consists of an FTIOIE with a two-element quad antenna following map have been firsts: G3RPB-TGOAA (26/11/67). , 18m above ground and a dipole. Bill has numerous trophies presented by G3 R lit-WOGTA/8F4 (Indonesia) 20/10/66 arid G-3RP13:-.Z158-J various countries for his callout work on St Helena—he is in touch with (3/12/66). G3MCK has also contributed by providing information from the air-sea rescue services and has taken part in many yacht rescues. He is Short Wave Magazine of December 1953 which records what is probably a member of RSGB and enjoys working UK stations, but points out that the first G-ZL contact when G6GM worked ZL1AH on 16/10/53. G3RPB sometimes the QSL cards are a little slow. All supplies for the 47 square- believes that the first UK-Australia contact took place either between mile island are imported by sea and there is no proper harbour— G3PU and VK5K0 or between G3FPQ and VK3BM in the early everything has to be transferred to lighters and taken to the quay for 'sixties—more information would be appreciated! unloading. The "firsts" challenge has also produced a letter from GM3UPT, who Michael Button, G4COA, is in N Dakota and using the callsign used to be VS5DB. He lists the stations he managed to work from Brunei G4C0A/WO. He has been in Grand Forks for about a year studying at the between periods of very high QRN. These were VS6D0 (9/1/76), nine JAs University of N Dakota, and will be very happy to work anyone who needs (10/1/76), JAIEOD (19/1/76), 9M2AX (23/1/76) six more JAs and a N Dakota QSL. His address will be found in "QTH Corner" W6RW (24/1/76), WA6NGG, W6QJD, W7DL, W7QID and VK6HD Vincent Lear, G3TKN, will be in St John's, Newfoundland, between 29 (24/1/76), and W6RW and W6AJJ (31/1/76). July and 25 August and on the air as G3TKN/V01, mostly on the higher frequency bands looking for UK contacts. If space permits he will also operate on 3.5MHz. Vincent thinks it worth mentioning that his licence Prefixes was free and produced on sight of a photocopy of his UK licence together The comment in "DX news" in March MOTA to the effect that ITU has with information on the address from which he intended to operate. The decreed that there should be two numbers in prefixes with only one letter address for other applicants is: Regional Director of Dept Communica- has caused some comment and confusion—not least to the writer! A more tions, Sir Humphrey Gilbert Building, Room 612, Duckworth St, St correct interpretation would seem to be that a second numeral is required John's, Nfd, Canada. where the country is indicated by a single letter and one numeral, je T3 in- In a letter to your scribe, Tom MerrilIs, ex-A4XHU, says that he is now dicates Kiribati and a second number is required, but G followed by any home from Oman and using his G3VBS call again. He apologizes to those number indicates England and does not need to be further elaborated. waiting for A4XHU QSLs as he has now run out of cards until his baggage arrives in the UK. He will be departing for Tanzania shortly. G8NS has recently returned from the Cayman is and reports that Alan Heard Island DX Association Kimble, ZF1AK, is retiring to his old home area in Devon in the early A press release from Jim Smith, formerly P29JS and now VK9NS, says autumn. that although the spring expedition to Heard Is had to be abandoned due to the short time-slot during which it would have been possible, all plans Dxpeditions are in hand for VKOJS to appear on the air this autumn. There were 256 A letter from Iris and Lloyd Colvin, dated 31 March, and written after donations recorded at the time the release was written, in addition to odd their return to the USA following their Caribbean expedition, said that small amounts. Jim has confirmed with the authorities that permission will between 12 October and 8 March they had made 55,000 QS0s operating most likely be granted at the appropriate time and the VKOJS licence will from W6KG/SV9, W6QL/SV5, W6KG/4X, FGOFOL/FS, FGOFOK and be kept valid. All those who sent donations are thanked and it is FMOFOL. From Martinique they entered both sections of the ARRL DX emphasized that anyone requiring the return of a donation should write to Contest and made about 5,000,000 points, They expect to return to their PO Box 103, Norfolk Is, Australia 2899. expeditioning in the autumn and are looking for help in obtaining permis- sion to operate from really rare places. DX News Sheet says that there is a rumour that N2DT, WODX and Awards others may visit Desecheo 1s—exact dates were not known and the opera- The RNARS Anniversary Award tion may well have already taken place. To celebrate the 21st anniversary of the forming of the Royal Naval VK2B1L, VK2BKD and VK9NS were expected to be on the air from the Amateur Radio Society on 25 June 1960, the society has instituted an Tokelau Is (ZM7) late in May or early in June. Activity would be mostly award to encourage communication between society "special event" sta- on 14, 21 and 28MHz cw and ssb. tions, RNARS members and all radio amateurs. The award is available to all licensed amateurs and listeners for contacts/reports between 1 June 1981 and 31 May 1982. UK and Eire applicants require contacts with, or Zimbabwe A press release from the Zimbabwe Radio Society gives the news that new ground was broken on 2 March this year with the start of a formal training course for those intending to take the RAE. Amateur radio in Zimbabwe has until now had a fairly limited following—in May 1980 there were about 120 licensed amateurs, and the total society membership was under 200. The more peaceful situation in the country and the introduction of a citizens band service have caused interest to increase dramatically. For practical reasons the size of the class had to be restricted to 27 and adver- tised solely by word of mouth (in spite of this the course was over- subscribed on the first day) and the students consist of 14 Africans and 13 Europeans. The release makes special mention of Peter Strauss, ZR6M1/A22PS, for his encouragement and advice based on previous ex- perience in southern Africa. Chief lecturer is ZEIFY, who is assisted by ZEIFI. ARRL generously donated enough handbooks to provide each stu- dent with his own textbook for the course, and the Dept of Electrical Engineering of the University of Zimbabwe kindly provided the ideal venue for the lectures. The ball is now firmly in the ZARS court, and it is hoped that there will be 27 new ZE callsigns on the air before the year is out. Problems still re- main one of which is the difficulty in obtaining radio equipment or even Bob Black, WA4SKE, in the shack of G4FKJ during one of his twice-yearly components—importation is strictly controlled due to currency shor- business-cum-pleasure trips round the world. He can usually be found on tage—and donations would be greatly appreciated. The ZARS address is 21.362kHz from 1800 to 1900gmt. and on 14.280kHz from 0600 to 0700gmt. PO Box 2377, Salisbury, Zimbabwe. operating from amateur stations in countries which he visits

RADIO COMMUNICATION June 1981 543 CITH CORNER 28,025 and 28,500kHz, (as well as 50,100, 144,100 and 146,520kHz). A AO2HA M via EA20P, A. R. Echevarria, Vg Begone 12, Bilbao 6, Spain. recommendation is made that phone should be used during even hours ex.A4XHU T. Merrill, 14 Cross Sr, Springfield. Oldham, Lancs. (gmt) and cw during odd hours. Logs should include duplicate sheets and a A4XIU via G4GIR, I. C. Frith 13 Rye Crescent. Cople, Bedford MK44 3TJ. CP6EL A. Pauker, PO Box 470, Santa Cruz, Bolivia. summary sheet showing a chart of multipliers per band/mode and score CR9BE JA1UT, Y. Hayashi, 4.20.2 Nishi•Gotanda. Shinagawa. Tokyo, Japan. calculation. They should be sent to Canadian Amateur Radio Federation, FR7AI/G via OF2OU, Ursula Riechmann. Goldflegge 3, D 4992 Espelkamp, W Germany. NH6D/KH3 via NHED, W. Myerson, 94 208 Kealohi St 172, Mililanitown, Hawaii, 96789. 203-1946 York Avenue, Vancouver, BC, Canada, V6J 1E3. Photocopies ADOS/KH5 ADOS. G. Carleton, Box 43, Merrifield, Minn, 56465, USA. of the summary sheets are available from G3FKM (sae please). ADOS/KH5K} TYA11 via ON5NT. G. Penny. e Lindestr, 13•98130 Aaliar, OV, Belgium. VP8AEN via GM3ITN. L. Hamilton, Halls Land, Hardgate. Clydebank. Glasgow. The Second European Fraternizing QSO Party 1981 VP8AGX via G4JDT. 0800 to 1000 and 1200 to 1400 20 June. VS5PP Al Cantley, PO Box 1200. Bandar Sen Bangawan, Brunei. W3USS Capitol Hill ARS, P. Huber. Box 73. Office of the Senate Supt. Washington, The first period will take place near 3,560kHz, and the second near DC. 20510, USA. 7,030kHz. CW only. Exchanges consist of RST/QTH/name/club name G4C0A/WO M. Botton, 6A Brannon, Grand Forks, ND, 58201, USA. XT2A W via KNIDPS, D. Goderre. Baltic Rd. Franklin, CI, 06254. USA. and number. Clubs include SCAG, AGCW, G-QRP, TOPS, SARS, HSC 5134R W Ray Woolley, BEMRS. BFPO 53. and CWC. There arc three categories: M, members; N. non-members; and 5H3AA PO Box 83, Sago Moyo, Tanzania. 807BG via DK4KY, K. Hippel, Hackenbg Zum Knollen 21. Bergneustadt 1 D 5275, W S, listeners. Stations may be worked once on each band. Members of listed Germany. clubs score three points for QS0s with their own country and five for those with other countries, "N" entrants score one point per QS0, and reports of, five special activity stations and 20 RNARS members; other "S" one for each complete contact logged (both exchanges). Send logs to Europeans three and 10; and others one and five respectively. Apply with reach Karl-Heinz Paape, DJ5ZP, Lauterbacher Str. 11, D-6840 certified log data plus 0-50 (for UK) or CI or 10 ircs (all others), to T. Waechtersbach 1. W Germany, no later than 31 August. McCrimmond, G4LQM, 6 York & Albany Close, Walmer, Deal, Kent. RNARS members tend to operate around 1,820, 1,860, 3,520, 3,660, 7,020, 7,090, 14,052, 14,140, 14,340, 21,052, 21,190, 21,433, 28,052, Around the bands 28,400 and 28,933k Hz. Some of the special stations due to be active during The G8KG summary for April reads as follows: "The first three weeks of the month saw a very high level of solar activity with many sunspots, a the year are GB2RN, GB3RN, GB4RN, GB3RNR, GB4RM, GB8RM, large number of flares, and high 2,800MHz solar flux values. At the time GB2MN, GB3CRS, VK3RAN and ZL2RN. of writing, the average solar flux for the past 27 days had risen to 232sfu The WACE Award having been near to or above the 200 mark for 60 days. Daily values were The Worked All Chile Award is issued by the Radio Club de Chile to all above 250 from 8 to 15 April, with a high of 276sfu on 10 April, making who have established two-way contact with CE stations in each of the 10 this the eighth month of the cycle to show peak values above 250sfu. This zones into which the Chilean territory is divided (CE I -CEO). All contacts peak of activity was accompanied by a major geomagnetic disturbance on since 1922 are valid and all must have been made from the same country. 11 to 13 April, with Boulder reporting an A-index of 105 for the latter Applicants should send a list of QSLs (certified by a recognized radio club date. or national society) giving callsigns, date, signal reports and mode, plus "The provisional SIDC sunspot number for March was 133-8, so that eight ircs to: The Awards Manager, Radio Club de Chile, Casilla 13630. the three-month mean values centred on December. January and February Santiago de Chile. (Note that these are new rules for this award effective were 146, 145 and 130 respectively. This represents a rather steep fall from from December 1980.) the November 1980 value of 162 but it looks as if the curve may be about to level off or even rise again in March and April. It is also interesting to WAB Awards note that, in terms of solar flux, there has been no significant fall in the A further clarification of the administration of these certificates: G4KSQ mean level over the past 12 months or so." has confirmed that the awards manager is K. Draycott, G3UQT, 175 In spite of the abnormally early deadline for this month's MOTA the Oliver Road, Kirk Hallam, Ilkeston, Derbyshire DE7 4JW, and that all following sent in contributions to this part of the column: Gs 2HKU, 3HB, applications should be sent to him. Book sales and other information are 4QK, 5JL, 3AAE, 3GHY, 3GIQ, 3GVV, 3HCT, 3IM W, 3KSH, 3LPS, handled by Mr B. J. Morris, G4KSQ, 22 Burdett Avenue, Sandhills Estate, GM3LYY, Gs 3NWG, 4AXD, GD4BEG, Gs 4EHQ, 4FKU, GW4KGR, Headington, Oxford OX3 8ED. G4LRS and RS 1066. Stations listed in italics were using cw. Contests -11MHz. 0000 EF6BDX I= EA6), EG5HM, UAlCIN. 0300 KP4ES, W 1JZ. K2B0. The All Asian DX Contest 0400 VE1AXT, UA9FCG. 0600 EA9EU, EF6BDX, VV8LRL. 2100 UA9XCF. 2200 EASAIO, HB9PR, I5Y7; ZD8TC. 2300 AO2HAM, OHOXX/OJO, G4.1VG /OHO. 0000 20 June to 2400 21 June (Phone). 3-5MHz. 0400 KP2A, VP2VHK. 0500 EA9EU, LU3AJW, VP5RFS, ZP5PX. 0600 0000 22 August to 2400 23 August (CW). EG9IE, HI8LC, HK, HP, 0A4AWD, PY, W2-W4, W6, ZF2E0, ZL20M, ZL4KF. 0700 All bands 1-8 to 28MHz. Single-operator single-band or multi-band and 6W8AR . 2000 RG4C, UK7LAY, UK9CAE, 7X2HM . 2100 AP2P. 2200 J5AG. 2300 multi-operator multi-band categories. Exchanges consist of RS/T plus two J5AG, OHOXZ/OJO, TU2HH, 741,77 7MHz. 0000 G3KTRI5N9. 0100 AA7C, FGOGDI/FS 1GSL via F6AXX), J87BL, figures denoting the operator's age (ladies send "00"). QS0s with Asiatic KL 7V, UK, Ul, t/J, UM, N6YK/VP2A (OSL to N6NK), VP2ED, VP5IDT (OSL to stations on I -8MHz count three points, bn 3-5 and 7MHz two points, and WINGS). VU2TS, 2D8RH, 8P6MI (OSL to VE3JTO), 9K2DR, 9L1SG IOSL to on other bands one point. The multiplier is the number of different Asian prefixes worked on each band. Note that USA military stations (KA prefixes) do not count, and that JD1 (Minamitori Shima) is in Oceania, not Asia. Logs should list date, time, station worked, numbers sent and received, if multiplier and points claimed, and a summary sheet should also be completed. Photocopies of the latter may be obtained from G3FKM (sac please). Entries must be sent to reach JARL, PO Box 377, Tokyo Central, Japan, no later than 30 September (for phone) or 30 November (for cw). In the 1980 phone contest the only UK entrant was G3NFV who scored 7,800 points on 2IMHz. The Canada Contest 0001 to 2359 1 July. I- 8 to 144MHz, phone and cw combines. Single-operator single- and multi-band and multi-operator single-transmitter all-band categories. All stations may be worked-each one twice on each band (once on cw and once on phone). Exchanges consist of RS/T plus serial number (from 001), and VEI stations will also indicate their province (NS, NB, or PEI). Each QS0 with Canada counts 10 points, with other countries one point. A bonus of 10 points is gained by working any CARF official or a news station with the suffix TCA or VCA. Multipliers consist of the number of Canadian provinces/territories worked on each band and mode (a A group of those often found near 3,750k Hz II to Eddie, DJOSS /G4HWC; Tom, DJOBLUG 4CAG /MP4RFW /VS 9ATH /ZC4TH : Heinz, DLEAA ; and Ron, maximum of 192). Activity will be centred around 1,810, 3,525, 3,770, DA 1FR /G3NKO /DL2BL /DL5XF/MP4BFFIJMP4TBV /VS 2FN /VS9AFR . Photo: 3,900, 7,025, 7,070, 7,230, 14,025, 14,150, 14,300, 21,025, 21,200, 21,400. Kit, DA2WN /G4EIVIX /MP4BHT/MP4TCR

544 RADIO COMMUNICATION June 1981 DL6EV). 0500 W6-14/7. 0600 CO, HH2BM, HI, HK, J5AG, W6-W7, XE2MC, ZL. 0700 CP6ID, HKOF8F, VP2MGO, 14/6-W7. 0800 KL7GKY, VK50A, W6 W7, YS9RVE. 2100 J5AG, ZD8TC. 2200 A7XE, UAOOCA, UKOAMM. 2300 VP2M1X. 14MHz. 0000 HH2VP (QSL to N4XR). 0200 VP5RFS. 0700 FK8DR, F083 AG, FN, KJ6BZ, KJ7, VK2AGT. VKOJS/VK9. 0800 A35LG, CEOAE, FK8C1..1, J5AG, NH6D/KH3, W6MOB (in KH61, VR6TC, ZK1CG, ZL3AFFI / A, 51,N1AB. 1600 T3OAT, VO9AA, 9M6AH. 1700 FH8CO, HS5AID (QSL to AG6D(. ZL3AFHIA. 1800 FR7BP, KH3AB, VS6JW, 4K1C. 1900 FK8DO, N6HR/KX6, VP8SU, 9A1D, 9X5AB. 2000 XT2A W, VP8s QI, ZR, VK4NIC/3X. 2100 J5AG, W5JMM/SU 10SL to KA5AZT), TYA11, VK9CCT, VP8AEZ, 5V4HL. 2200 FGOGDUFS, JY8ZX IOSL to 18YCP), TA1CT, XT2A W, 4U I UN. 2300 J3AJ, TA2TAT, W3USS. 21MHz 0600 FO8HA, JA (until 0900), KH3AB (QSL to KB7M0), KH6, VK (both until 0900). 0700 FO8DF. 0900 AO2HAM, ZLs, 9M2FR. 1000 C21BS, XT2AVV. 1100 HMOU 1QSL to JA6HNK), P29AC, 2K ICG. 1300 AH2E, DU6JF, KL718, OHOXX/OJO. 1500 DF3NZ/ST2, 4U1UN, 9G1HZ (QSL via WA2MRZ). 1600 JD1ALZ, VS6CT, W6-W7 (until 2000), 1700 A7XD, S79NLB, TF5TP, ZE3JOIORP (1W). 1800 FR7AI/G, VS5PP, 3,98CF, VK4NIC/3X. 1900 FGOGDI/FS, VS5TX. 2000 A7XE, A9XF, KL7, T3OAT, VEZ VK. 2100 FP8HL, VK9CCT, ZD8FS )QSL to K4FS), 5N6ENV. 2200 KP4KK/DU2 (QSL to WA3HUP), TYA11, VP5GT, V1J2BK. 2300 CE3AA, VP2VHL (QSL to N6DX). 28MHz, 0000 VK1FT. 0100 VK2PFF, VK2001/M, VK2WI, LU, PY, ZL2NP. 0800 JA, PY, TR8I.J. 0900 TL8CN, ZL, ZS. 1000 A4XAU, C21BS, JA, W, 6T1YP, 807AV. 1100 A4, AP2P, C6ANU, FY7BF, H44DX, HH2SD, P29, TJ1GH, W, 9M2GZ. 1200 Brigadier-general Kamchai Chotikul, HS1WR. president of the Radio Amateur H44BH, KL7, W. ZL, 5X5FS. 1300 D68AM, J5AG, KL7IB, W, 6T1YP. 1400 PJ7AR1, Society of Thailand (standing) In his shack during a visit by David Rankin, VP2M0, YCOZR. 1500 A9XDB, J73PP, N4ADJ/KH2 (QSL to W84CCT), TL8RC, 9V1RH, secretary of the IARU Region 3 Association VP8QD, YC3HI. 1600 C5ACG, DU7RLC, TF3DC/OX, VP1BEH, ZS6ANL/31216, 5K4LLM. 1700 WA1SOB /CEO, W6-W7, 9M20K. 1800 FGOG01/ FS7, KH6, VP2MFC (QSL to K1M, VP2VJ, VP5RPS, W6-W7, ZD7. 1900 KH600, KL7CYL, PJ2CZ VP10A, VP8NO, VR6TC, VS5PP. 2000 0A8V, T3OAT, VP8ZV. 2100 CEOAE, KH6IJ. 2200 VK (LP) 6W81H. 2300 CE3WD, KL 7EZ VK(LP), VP8ADE, VP80G, ZL4CM. Propagation predictions

Your scribe would like to thank all who sent in information for this June. July and August are typical summer months as far as dx is concerned. Condi- tions will be very poor. Only Africa and South America will be heard with certainty, month's column, and also the authors of the following for items extracted: and North America only under very favourable conditions during the evening. the Long Island DX Bulletin (W4UL/W2IYX), DX News Sheet (Geoff The worsening summer conditions will not be as noticeable on 21MHz as they will Watts), Long Skip (VE3B MV), QRZ DX (K5FUV), DX'press (PAOTO). be on 28M Hz. A certain compensation for the poor dx conditions are the summer- CQ Magazine (W1WY), D X NL (DI.3RK), Informacion DX (EA1QF), time short-skip conditions caused by sporadic-E which will make European traffic possible on 28 and 21MHz. and the D X Bulletin (EAIQF). The 14MHz band will remain a specific night-time dx band. Traffic with Australia Please send all items for August issue to reach G3FK M no later than 23 and South-East Asia will be possible occasionally during the afternoon but will be in- June and for September by 23 July. terrupted by European ORM (often via short-skip). DX will be possible on 7MH z when the longest part of the path lies in darkness, but again European ORM and static will interrupt traffic. During the day this will be an ideal band for local traffic without the dead zone, while 3-5MHz will be better for local traffic during the night. Dead zones will not interrupt 3-5MHz, not even just before sunrise. The mean provisional sunspot number for March 1981 from the Sunspot Index Data Centre was 133.8. Daily numbers range from 86 on 19 March to 184 on HF propagation study 30 March. The predicted smoothed numbers for July. August and September are 127, 125 and 123 respectively.

Band predictions for June 1981 26MHz 21MHz 14MHz 7MHz 3.5MHz 14 MHz JUNE 1981 {000001111122 OC0001111122 030001111122 003E01111122 000001111122 t UTC 024680246802 0246E0248802 024E80246802 024680246802 02468024%02 USA-East W1-4 6 M alli Mir ! EUROPE USA- West W6, 7 5 e Î MZ EZ =] i i ir— Moscow .1111.1221 545556566787 642111111367 3 24 ,, Malta .221112331 7587%668888 875211112388 +62 35 Caribbean 6Y 5,FM. T I S 1.111 MI MICa : , il f/4 , Gibraltar 11. 523565465776 8%422212468 1-13 3+ Brazil PY s si ' Iceland 2..122122343 865322122345 332... .. 2 A , ASIA South Africa ZS s 11111211 : 0 : ! CIEZE M ffl111111 Osaka 1121112331 .21.12573 2 SE Asia HS.9M2 s C I : , , = 22e1 MIIIII MII Hong Kong 1112%223643 3...1.12E87 32 Bangkok ...111.. 111. 212133334664 51...1.12688 135 2 S " , Australia VK CIIM =13 Singe ...111..111. 222344334553 61-1.12683 1 135 2 L ' , New Delhi .. 111111121. 223333335664 73 26139 3 2 Teheran _1222112221 335433346776 973 26% 62 1 3 2 Japan JA S : . i CI MIIIM MIZZIO Colombo _122211211. 333334445875 84.. .1.2 869 4 136 2 i Bahrain 1777773331 546433446787 974 2689 62 138 3 3 Time (GMT) 00 02 04 06 08 10 12 14 16 18 20 22 24 Cyprus " ..111111211 324655556776 987543345799 752 256 42 24 21 N Hz JUNE 1981 Aden 1.1323334433 756533456888 9851. _2699 64 136 3 3 OCEANIA USA- East W1-4. i Suva Cs) .1 .12. 3421. :1551 , Suva 111 3112 43 44%1 88 .1552 .261 USA- West W6,7 Wellington Is1 ..111 21 125421.. .74 2 Wellington III 2112 12 66561 57 44752 .175 1 2 Caribbean 6 Y 5, FM , T I S Sydney 110 1134321. ..3 212421..1326 31 E ZIM Sydney III 2 1 64352 16 32463 66 31 Brazil PY s 133112...112. 1 134 2 Perth 33455431. . , 461 Honolulu till .14321..12 South Africa ZS S AFRICA SE Asia HS.9M2 s Seychelles 1.1323334221 646534466776 ses. .. .2689 63 136 3 3 s Mauritius .1323444433 5.654%56888 9561....2689 64 136 32 3 Australia VK , Nairobi 211323446%3 75E844,3668E8 9972... 2689 .1% 32 3 s , , Salisbury 2..323565633 13547444%888 9975.. .2688 662 36 43 3 Japan JA , t , L , Capetown .. .22256563. 1..7%556884 73.52.. 2889 662 36 43 3 Lagos 21,222456743 864654448E98 99752...2689 663 38 43 3 Time (GMT) 00 02 04 06 08 10 12 14 16 18 20 22 24 Ascension Is ....32345641 55216444613E6 99752.. 1589 663 36 43 3 Dakar 211232354542 885684495888 99862.. .589 863 36 43 2 28MHz JUNE 1981 . Las Palmas ....1..1111. 522454466665 9987665557% 87521.. 157 542 24 • S AMERICA USA-East W1-4 S I ! 1 1 1587 663. 35 43 2 South Shetland 35442. 145687. USA- West W6,7 L C =I I iI 1e I 1 r I Falkland 1$ 244431 4 .2456897 944111..1589 663. 35 43 2 I Rio de Janeiro 21...2243442 886114455788 998521...379 663 25 43 2 Caribbean 6Y5,FM, T I S : ' EZE22 =21 Buenos Aires 21...1243342 8%4.44%887 998611..13% 663. 15 33 2 Brazil PY , Lime 1...1.111122 743342343357 937631.. 16 683. 1 33 s zeeem Bogota 1....1.11111 642343333248 997531....16 583 23 South Africa ZS S : EIMMIIIII MI M MIIIII Me : N AMERICA SE Asia HS. 9M2 s r , Barbados 1....1111122 743344333367 997631....27 663 2 33 Jamaica 1 11 631122232235 887531 5 363 3 s Bermuda 1 11 631113222248 8E0531.. .16 453 2 Australia VK e r , , L ! e e : M li New York 42...1111134 786421 .15 252 2 I I 1 Mexico 42. .121123 688421. .1 .52...... 2 Japan JA S . . Montrose 31. .1111124 786421 14 253 2 Denver 21 1 45531 1.22 Time (GMT) 00 02 04 06 08 10 12 14 16 18 20 22 24 Los Angeles 1 11 25641...1. .12 S Short path L ..Long path I =1 1-5days f2 =Z2 6-20days Vancouver 1 24631.1 2 Fairbanks 124421..1211 Openings on more than 20days in the month

RADIO CO M MUNICATION June 1981 545 G. Cluer, G4AVV*

Live incidents On 10 March Robert Cox, G3PLP, was called on 28MHz by Gavin Payne, 5N3PJR/G8WMO, who was working in Nigeria and who reported that a neighbour had had a miscarriage and needed a drug not available in Nigeria. Furthermore, in Sapele there was no telephone, thus there was no

chance of calling for help by conventional means. G3PLP contacted his Land•Rovers of Rover Rescue/Norfolk Raynet in Naples local police, who in turn contacted a local church-run depot which specializes in sending drugs to third-world countries. The depot contacted Raynet supplies London, where supplies of the drug were found and taken under police The long-awaited up-dated Rayne! Manual is now available from the escort to Gatwick, where British Caledonian held up a flight for 25min in supplies officer, Mrs Jane Balestrini, "Merrivale", Willow Walk, order to transport the drug to Nigeria. This prompt action by G3PLP and Culverstone, Gravesend, Kent, at a cost of £1.04, or £2.93 for three, incl 5N3PJR probably saved the life of any future baby born to the Nigerian p&p. They will also be available postage-free from Raynet stands at majoi woman, and also gained useful publicity for amateur radio. rallies. This edition has been bound in loose leaf form so that future Tim Thirst, G4CTT, controller of N Norfolk, has sent details of the in- amendment will be easy, and it will also be convenient for groups to insert volvement of Norfolk groups in a relief operation after the Italian earth- their own local information. quake last December. The local Rover Rescue Group, a group of Land- By the time this issue of Rad Corn is published, the new lapel badges will Rover owners, put their equipment to use by towing four caravans and a be available. These are black on copper, which is more in line with the trailer to the scene of the disaster, where the villages in need were in areas usual Raynet colours than the older badge which has been out of stock for where only Land-Rovers stood any chance of getting through, accom- some months. panied by Raynet members to provide communication. Raynct and Rover If you are about to send off a yellow and blue application form to Rescue raised over £3,000 to cover the fuel and other necessary expenses register or re-register as a Raynet member, please note that the 20p for for the journey, and many local firms donated money and equipment. The lamination of the membership card is no longer required; the RSGB has caravans, which as well as carrying the supplies needed by the villagers agreed to subsidize this. Please note that the photograph is still required. were left in Italy as emergency accommodation, were donated by the The committee has debated the necessity for this photograph a number of public. The radio escort proved invaluable when dynamo trouble crippled times, as it is aware that it is not always easy for prospective members to one Land-Rover until a call on S18 to a German amateur produced help have a photograph taken. However, as several groups and user services are from a British Military Police unit outside Düsseldorf. Local amateurs very keen that the membership card should mean something, and are con- were also called in to help sort out the red tape which had hindered the cerned to keep it looking professional, the committee has decided only to relief attempts locally and threatened to slow down the Land-Rover con- issue cards if a photograph has been attached. voy. Particular help was given by DJOZ.F and I8YCP who helped with repairs, local accommodation and general assistance, and to whom the News from groups team which went to Italy is particularly grateful. G3HRK says: "The co- in Scotland the local authorities are pressurizing local amateurs to form a operation between, and support from, Rover Rescue and Raynet, non- Raynet group. This is a pleasant change from the usual state of affairs Raynet amateurs and swls, European tv, the Norfolk branch of the Red where groups have to convince the user services that they can fulfil a useful Cross, businesses, organizations and schools in Norfolk, and the Italian function. GM3O WU is co-ordinating the formation of a group in Lothian, Embassy were absolutely fantastic. A great effort: well done, and thanks and anyone interested in joining him should contact him direct, QTHR. to everybody." Dennis Scott, GM41ZN, hopes to get a group started in Moray Firth & Speyside; his address is 3 East High Street, Portgorden, Buckie. Mark Raynet Com mittee Lees, G8XQB, is starting a group in the Manchester area, and those in- Raynet members will probably know from their controllers that the whole terested should contact him at 6 Haxby Road, Gorton, Manchester. Mr C. structure of the RSGB Raynet Committee is undergoing reorganization in I. Townsend, G8PUT, 77 Yews Hill Road. Lockwood, Huddersfield, is order to make it more representative of the membership as a whole. It is hoping to form a group in that area, and would like to hear from any in- planned that next year the committee will consist of a majority of elected terested prospective members, as would Gordon Coggon, G4FYE, of 13 members, rather than be wholly appointed by Council, and to assist in Bardolf Road, Cantley Estate, Doncaster. deciding the exact form of the representation the following corresponding The West Sussex Raynet Group continues to send the writer its very pro- members were elected to the committee for this year: Midlands—Doug fessional newsletter; from it we note the birth of the Mid-Sussex Raynet Willis, G3HRK; South—Bill Colelough, G3XC; Greater London—Jeremy Group, helped by G8VKQ and G8MDP. The contact for West Sussex is Wilcox, G4GBW; North—H. R. Christopher, G3VBI; N Ireland—J. T. G4BLJ, and this group seems to be making good use of the recent permis- Barnes, GI3USS, Wales—S. J. Brennan, GW3ZXI; and Scotland—D. E. sion for Raynet to use manned talkthrough stations. What other groups Carrington, GM3RFA. are active in this field? Mr E. Walton, G4FSN, has replaced Julian Maud, who has had to I am grateful to G4GKL (Oxfordshire Raynet) and G4CTT (N Norfolk) resign from the committee due to the pressure of business. for their reports on recent exercises.

A Raynet symposium was held at County Hall, Truro, Cornwall, on 4 April. Seen here facing the audience are II to rl: D. A. Evans. G3OUF, RSGB general manager; B. O'Brien, G2AIVIV. RSGB President; W. Colclough. G3XC, Raynet county controller; D. Fisher, G4IGN. deputy controller; E. Yeomanson, G3IIR. Raynet Com mittee chairman; and A. Webber, operations controller, AHA am- bulance section: Photo: G8YOQ

•12 Bingham koad. Addiscomhe. Croydon CRO 7E11.

546 RADIO COMMUNICATION June 1981 microcomputer programs, ASCII is far more suitable are to be thanked and praised by all, their services are because it is fast. The W1A W bulletin in baudot takes second to none. about 15min; in ASCII less than half that time. South American ORM is the cross one has to bear in It is not easy when offering criticism to avoid this part of the world if trying to work north-east to engendering a feeling of hostility in the recipient. As I south-east. My sympathies go to the VP8s and anyone write simply to give information which appears to be else in similar circumstances. Oh to operate where novel to Gerard, I hope he will not take offence. there is no-one behind you! Incidentally, I have ¡ust received front France a My advice to people trying to work a rare station is to modification for the Elekterminal which permits both be patient, not rude. Call when no OSO is taking baudot and ASCII. Such a system would still be place- and remember, it is not always the loudest call simpler to construct than the notable G3PLX design, which is picked up, but the clearest and the one which and it would permit both codes to be available at the is timed the best. We try to help, but rapid frustration touch of a switch. sets in when there is no consideration given, thus in- Finally, may I suggest that most serious experimen- creasing the chances of pulling the big switch. CO MPUTER DATA TRANS MISSION tation is worthwhile: minority projects like Amtor and Guy Barnish, J6LOU STANDARDS ASCII may, thereby become (as did ssb) the mode of The Editor the future. Radio Communication R. F. C. Brake, G8QR AGAINST HA MSPEAK Sir-1 read with interest the com ments on computer IASCII may not be legal on trIMHz— G28VN) The Editor data transmission standards (Rad Corn February 1981). Radio Com munication I should like to suggest a frequency shift of 880Hz, us- Sir—Speaking to people across the world by means of ing the two tones 1,275 and 2,155Hz, at a baud rate of EQUIPMENT COSTS the magic of radio is an extremely pleasurable ex- 976.56 as an amateur data standard. The Editor perience and gives me great satisfaction. We British I expect that 300 bauds will be the most popular Radio Com munication are fortunate to find that our language is used as an in- speed, as so many computers have it available already. Sir—The suggestion by Mr Maling, G5JL, ("Your api• ternational means of communication. In choosing a com mon higher speed perhaps we Why then do we wrap it up, camouflage it, and en- should look for one that is also readily available on nion" Februaryl that a decent 100W cw rig can be manufactured and sold for E100 retail, including VAT, code it in a lot of meaningless claptrap jargon? It is very most computers. suggests that he is rather out of touch with the realities sensible when using morse code (please not cw) to The vdu sections of most home computers produce employ codes such as 0TH or 73, but when using a form of 625-line video. I have a Nascom 2 which pro. of business life. The selling price of any equipment must take into account the following, to list a few: speech what is the point? duces 312 lines in 50.08 fields per second, but it does design, development, prototype manufacture, testing, When I talk to a friend on the telephone what would have a line rate of exactly 15,625Hz which, if fed into market research, selling, advertising, after-sales war- his reaction be if I said "Hello 'om' how is the 'xyl'? I the (16 ) clock input of its UART, will run it at 976.56 ranty and service. The market for a cw-only rig is must leave the 'shack' because I am 11SYing' to 'DJ bauds. If this precise frequency is not available from a relatively small, and high-volume production techni- land' 73s and 88s'?" He would think I was crazy. computer's vdu it can be synthesized by dividing a ques would not be appropriate. Production would very So let us all agree to use plain English when we talk 1MHz oscillator's output by 64. likely be labour intensive, with its attendant higher over the air — let us use "conversation" instead of Generating the two tones by variable division of a costs. Any such equipment must be designed and built "OSO" (American "KE WSO W" even worse), "loca- crystal-controlled oscillator's output is a useful to high technical standards to comply with current tion" instead of "OTH", and "wife" instead of "xyl". It method, as it needs no line up. Fortunately the lower legislation and safety requirements. I would invite Mr is quicker, easier, more natural and more easily frequency rtty tone 1,275Hz can be synthesized by Mating to submit his developed design for a nine-band understood. Roger? dividing 62.5kHz by 49. Again 62• 5kHz may be cw rig, complete with integral vfo and power supply for Harry Kleeman, G4BHY available from the computer's vdu section. I have sug- appraisal. A hybrid design using solid-state high stabili- gested 2,155Hz for the upper tone because it too can ty vfo and driver stages followed by a pair of 6146 B be produced from 62 -5kHz by dividing by 29. tubes would seem to fit the requirement. If he can CB The old rtty wide shift upper frequency of 2,125Hz The Editor demonstrate that this can be put into limited produc- would need a source of 2MHz to be synthesized ac- Radio Communication tion, say a few hundred, and sold profitably for around curately, but more importantly the circuit would con- Sir—I fully agree with Ken Gray that the cb invasion of £100, then my company will consider it as a proposi- tain more components. All existing receiver circuits the lower section of the 28MHz bands causes great tion— and maybe give him a share of the profits. would only need to be retuned by 30Hz, which may not concern. I have overheard a local cb operator commen- E. W. Surgis, G6F8 even involve modification to the circuit, only adjust- ting that he had heard another cber from the ment. Maidstone area as high as 28.4MHz. He had the G5JL com ments: As a postscript, to operate 45 baud rtty via a UART audacity to remark that amateurs did not use the lower Yes, £100 was a bit optimistic, but at least it provided a utilizing 31. 25kHz which is also to be found in the vdu part of the 28MHz band! debating point! But a cw transmitter is basically a sim- section of a computer: We must use the cw segment as fully as possible and ple concept. So many things are possible electronically 31,250/43 = 16 x 45.42 make our presence known, otherwise these illegal now that designers get drunk with power and pile com- Andrew Sturt, G8SIK operators will land are) overflowing from the already plication on complication. A return to simplicity and II overcrowded, still illegal, cb 27MHz band. The danger The Editor hope) lower prices might well produce its own market. will, as I see it, be particularly serious during periods of Radio Communication J. J. Mating, G5JL Sir —I refer to Gerard Bulger's statement in the low activity when 28MHz tends to be neglected. February Rad Corn that "it would be ill-mannered and Many of these illegal sets are multi-channel and in- bad amateur radio practice to use ASCII... on the DX OPERATING clude part of the 28MHz amateur band. A local radio amateur bands". His reason seems to be given in The Editor dealer is also displaying 49MHz hand.helds in his win- paragraph numbered 4; ie ASCII is "a system which is Radio Communication dow! totally incomprehensible to other amateurs". Both Sir—The article "DX operating - an introduction" (Rad We are all indebted to the RSGB for protecting our these remarks are opinions, to which Gerard is entitled. Corn February 1981) was very interesting from the interests, and we feel assured of your support all the They do not, however, seem to accord with the facts. "searchers" point of view, and VP8VN's letter publish- way. Over the past year I have been experimenting with a ed in the same issue had several salient points from the Ernest Jack Bonner, G8LZ simple ASCII system, comprising the Elekterminal, an opposite side of the antenna. STS demodulator and a crystal tone generator. In the May I add some com ments from a "wanted call" GETTING HOLD OF THE WRONG END last three months I have had excellent OSOs with over which have bearings on both articles? The first point is OF THE STICK 80 different stations in four continents on 14MHz. that we are all amateur operators and not answering The Editor ASCII is, therefore, not "a system totally unintelligible machines; some of us like a chat and few of us like Radio Communication to radio amateurs". Indeed, there must be more sta- "breakers". Talking of "breakers", it is well known that Sir—As hi-fi dealers we have, like most, been inun- tions capable of using ASCII at 110 bauds, 170Hz shift Europeans (including Gsl are the rudest operators dated with complaints regarding cb breaking through than there are stations using Amtor, a system of which when it comes to working pile-ups or wanting a rare on hi-fi, and in self-defence have made up a window Gerard approves. One could, indeed, apply his own station. They have no compunction about breaking in, showcard with antenna filters, ferrite-cores etc on it. criticism to Arntor: most amateurs cannot copy it, causing ORM and thus lengthening the OSOs. If you We thought the wording was fairly clear until the therefore it is ill-mannered to use it. want confirmation of this, just listen in to the DI( 2 OC morning when a customer came into the shop and re- There is this further: although the G3PLX design for net when the net controller is assimilating his list of dx quested, "One of those devices you fit to your hi-fi to baudot has become deservedly widely used, it is more stations, or asking them to make their calls. It is also enable you to listen to cb." complicated in design and construction than the well known that the Japanese are the most polite It made our day, and seemed too good to keep to Elekterminal/ST5icrystal tone generator. Moreover operators, and my own experience is that the mid- ourselves. the latter gives scroll up and full cursor control without West and Western USA operators are similarly polite. Holdings Photo Audio Centre additional chips. The com ments on OSLing by G3XTT are particularly My own system was originally a pure piece of ex- apt, and I am quite sure that many dx stations are as perimentation and I realised at the outset from my ex- grateful to him as I am for pointing out the problems HELP WANTED perience with the Creed 78 that it might prove difficult we can experience. St Lucia is one of the countries The Editor to make any contacts. When, however, the system without a bureau, and if amateurs would listen for OSL Radio Com munication was finally put on the air I found plenty of stations will- information- instead of just blurting out "I'll OSL via Sir— I would like to hear from all those amateurs in the ing to have a QS0 in ASCII W3JF estimates that the bureau" and then going OAT they would get bet- United Kingdom who have experimented with the third perhaps one third of the users of rtty in the USA are ter service and cards would not go missing. OSL method also known as the Weaver method) of capable of using ASCII. Further, W1A W puts out the managers stand as a race apart, and many of us ¡ust generating ssb signals. I have a great deal of informa- official ARRL news in baudot and ASCII. could not function as well as we do without them, par- tion to share with interested amateurs, including a May 1 suggest, therefore, that Gerard has been a bit ticularly in the absence of bureaux. They provide a fan- bibliography of over 120 references gleaned from hasty in arriving at his conclusions. tastic service, generally at airmail speed, which costs assorted publications worldwide. Also interested in With the arrival of the new HAL. the Robot and the money, and two ircs is a small price to pay if you really compandored audio. Theta, not to mention amateurs using dedicated equip- want the confirmation. There is also the added corn Interest in experimenting is, alas, dying in North ment and microcomputers, one might venture the opi- pensation that C1SLing via managers is almost 100 per America but is alive and well in G-land. I need help in nion with some justification that ASCII is the corning cent guaranteed, whereas this is not always the case if this matter from your readers. mode. Certainly for people wishing to exchange you deal direct - as I know to my cost! OSL managers C. B. Smith, VE3IEN

RA DIO CO M MUNICATION June 1981 547 SINGLE-OPERATOR SECTION Band Poen CallsIgn 0111 Score pean Points CISOs Boat dx Km 1 G3YTE AL13 1,158 A 12 764 118 DKOLF 447 B 1 461 71 F6KNO 506 2 GJ4ICD YJ70 1,003 A 1 4,821 408 DLOTR/P 657 3 G3UBX YM40 989 A 44 8 2 G3PIA/P 140 B 2 455 79 GM3ZXE/P 466 4 G8TFI ZL38 762 A 10 1,100 231 F6FGV/A 688 B 3 246 58 PAOSON 417 5 DK3UZ EN20 666 A 2 3,210 248 OH4PU 1354 6 G8ADM ZL63 635 A 4 2,069 432 DJ8PB 570 B 5 95 29 DC6MV 515 7 GJ4JWA YJ70 558 A 3 2,738 241 G4AXL/P 659 March 1981 144/432MHz Contest results 8 G8GXE ZL48 514 A 41 22 20 GW8WDC/P 246 El 4 229 63 0C6MV 474 This year the contest was reduced from three to two bands in an attempt to lessen 9 G4AHN ZL56 402 A 5 1.939 321 GM3PXK 530 the amount of equipment necessary for the event. This move was welcomed by the 10 GMBYJU Y005 387 A 6 1,866 198 F1K8F/P 560 smaller groups and by many single-operators, but the larger groups still felt frustrated II GIBT130 X033 294 A 7 1,416 126 ON72X/A 710 by the limitations of the one-callsign rule. The idea of having a single-callsign section 12 G4ARI 2M24 267 A 8 1.287 262 ON7CC 437 13 G3TOU AM66 235 A 9 1.13s 153 DLOEE/P 615 is sound but it seems that there is also a place for a two-callsign section. 14 G3FIJ AL05 229 A 15 622 102 014D8B/P 617 It was apparent from the 427s and logsheets that more than just a few had failed to B 9 46 10 G8AGU 342 read the rules carefully, in particular Rule 12; as a result points were lost. The demand 15 G8XNR 7148 210 A 22 459 119 F6KCP 376 from several stations for a multiplier on 432MHz showed that Rule 8b had not been 8 6 53 34 F6KBF 162 appreciated. 16 G8RBY ZM16 207 A 11 997 196 GM4JLY 488 Nevertheless the number of entries increased this year. In the multi-operator sec- 17 G8SKG ZN68 206 A 13 659 93 F1KNO 676 tion half the entries were two-band as were a quarter of the single-operator section. Et 10 32 8 F6KBF/P 337 18 08X81-1 ZL50 134 A 39 169 63 GW30X1)/P 222 To achieve a winning score it was essentiel to operate on both bands. 6 7 51 31 G6GN 175 Com ments on propagation varied from "very good" to "atrocious" depending on 19 G8HHOPA 2L42 130 A 14 629 153 PAOTHT 592 band and location. Most stations made some good contacts and for the observant 20 G8POT ZM41 126 A 16 606 148 ON7ZX/A 400 operators these were by auroral propagation early in the contest. The best "A" dx 21 GW3NYY XL40 122 A 17 597 81 ON7ZX/A 515 was DK3UZ to OH4PU at 1,354km. U G4KGC ZM65 120 A 18 579 133 ON5UM/A 415 23 GBNCC 2M62 115 A 23 4.47 96 PEOMAR/P 398 Congratulations and certificates go to the five winning stations. 8 12 10 4 GVV30X0 1 P 105 G3VPK 24 GBLXY 2109 114 A 37 129 53 ON7ZX/A 293 8 9 40 23 PEOMAR/P 307 MULTI-OPERATOR SECTION 25 GI3UAG YM50 112 A 19 538 109 DKOLF 615 Band• 26 G4CIFI AL41 108 A 20 522 99 DB6DC 480 Pean CalleIgn GTH Score posn Points 0605 Bast dx Km 27 G3JFY ZL73 102 A 21 492 98 PA3A0N/P 435 1 G3P1A/P ZL33 1,545 A 2 3,657 510 GM3J1J 875 29 M M' ZM41 71 A 24 342 88 GJ4JWA 350 B 1 626 89 DJ9DL 630 29 G8TLC ZM25 67 A 25 325 80 GM4JKL 414 2 G3ZIG/A AM17 1.183 A 12 2,721 277 DK3UZ 591 33 G4AGO ZL66 EA A 26 307 103 FIFHI 456 B 3 487 79 DBOAP I A 545 31 G6AYY XK38 63 A 27 303 43 F6APE 430 3 GYV30XD/P YM54 1,160 A 5 3.519 457 PAOMIR 620 32 G4FKS ZN13 62 A 28 293 65 G6HH/P 358 8 5 396 59 ON7WR /A 592 33 C,8X0S/A ZMO3 61 A 29 292 60 F1KBF/P 320 4 G5M W/P AL43 1,054 A 13 2.430 355 DKOFU 652 34 G8XYM ZN13 57 A 30 274 36 FIKBF/P 400 B 4 458 72 DJ9DL 460 35 G8AHK ZL68 51 A 31 246 81 C,8JML 331 5 G6HH/P AK03 1,000 A 1 6.714 660 DK3UZ 703 36 C,8DIU ZL60 50 8 11 23 13 G6YB/A 240 6 G4BRK 2N468 942 A 30 1.090 192 DKOLF 520 37 G4HYG YN28 48 A 32 229 39 G8TAK 290 B 2 488 82 •DJ5GR 485 38 G8ZVL YK38 46 A 33 223 67 E190 349 7 G4DEZ/P AL24 916 A 7 3,246 440 DL212/4 651 39 GBORX YL49 45 A 34 215 43 ON4AVV/A 350 13 6 271 37 DL4VZ/P 504 40 08XTJ ZL27 41 A 35 198 54 GRXLV 236 8 GFIZHP ZM29 901 A 6 3,502 363 OK828 713 41 G4KVI 2137 29 A 36 142 42 F1KNU/P 270 8 7 237 37 DL4VZ 626 42 G2WS YL56 24 A 38 117 27 040EE 252 9 G3LTY/P AL55 712 A 8 3,086 392 DKOUL/P 618 43 G8TZJ YNO7 23 A 39 109 21 G8ADM 310 B 13 158 30 DJBPB 406 44 G8YG W ZL56 9 A 41 42 16 GJ4JWA 250 10 GW8W0C./P YN75 632 A 11 2,948 449 ON7ZX/A 514 B 16 121 27 F-6K8F 400 11 G2BRS/P YK19 595 A 4 3,565 447 F6BSJ 690 RECEIVING SECTION 13 21 41 11 G8HOM 235 Poen Ganelon 0TH Score Band* Points 1360s Best dx Km 12 G6YB/A YL47 581 A 23 1,488 230 PAOPLY/A 515 1 BRS32525 AL41a 683 A 625 168 F6CJG/P 640 B 8 225 39 ON5U1 443 B 58 22 C,8AGU 270 13 G4KKC/P ZM80 559 A 27 1,368 298 F1KNO 518 2 8RS15822 2L40j 436 A 430 119 PA3AGN/P 320 B 9 222 50 DC6MV 440 8 6 4 - - 14 G8RZP 2148 547 A 15 2,364 451 F6CJG/P 728 3 BRS26003 Y023e 359 A 359 43 G6HH/P 491 8 15 122 36 PEOMAR/P 393 4 BRS28198 AKO4h 292 A 263 41 DF3EH 400 15 G4ERP/P 21.01 540 A 3 3,624 590 F1KNO 618 8 29 7 G6YBiA 225 16 G3YMO/A AL76 451 A 9 2,977 346 GI4DBB/P 678 5 BRS44997 YN68g 128 A 128 50 GJ41C0 433 B 26 5 3 G3YTE 93 6 BRS44115 - 72 A 72 30 - - 17 GW4GMO/P YLD5 441 A 10 2,961 481 F1FHI 560 18 048 VV YM79 440 A 26 1,425 287 PEIBNK/P 503 Check logs acknowledged with thanks from- G3EIPM. G3HRY. G4CTI. 080KK, G8PX8/P. B 14 143 40 PEOMAR/P 440 G8WDI, G8YCI. 19 G4EKE/P YK 19 428 A 37 777 118 PE1GJA/P 543 B 11 195 45 03210/4 323 20 G4AXL/P YP69 393 A 18 2,036 222 GJ4JWA 632 8 20 48 20 G5M W/P 490 21 0861 YM50 379 A 41 588 124 ON5UM/A 486 B 17 119 26 PEOMAR/P 420 21/28MHz Telephony Contest results errata 22 G3XBF/P AL21 357 A 20 1.860 351 GI4GVS 515 It is regretted that two stations were omitted from the results table published in the 8 19 50 7 031-1HI 75 23 G3UFB/P 2117 346 A 19 1,947 389 DL9GS 548 Apr il issue of Radio Com m unication. El 23 35 16 GIAGOXD/P 152 To the two stations concerned, G3UOR and G4JYL, the adjudicator offers his 24 G3GW8/P 2M54 332 B 10 208 57 PE1BJW/P 380 sincere apologies. G3UDR, with 357,871 points, should have been placed in fourth 25 G3SFG/P ZL29 320 A 14 2,418 452 0140813/P 567 position, and G4JYL, with 129,978 points, in 21st position. The positions of other 26 GW8JUL/P YN75 319 A 16 2,141 184 ON5UM/A 576 contestants should be adjusted accordingly. 27 G14DBB/P WP77 318 A 25 1,438 129 F1K8F/P 738 8 18 65 10 G3UBX 408 28 G3AM W ZN19 311 A 17 2,085 164 GJ4ICD - 29 G8IZR/P YN3B 300 8 12 188 32 08M W/P 347 30 G8W28 / P AM64 282 A 22 1,502 214 F1KNO 538 8 u 36 14 PEOMAR 236 Affiliated Societies Team Contest 1981 results 31 G8LED/P 2M54 255 A 21 1,715 3E8 014088/P 450 The continuing popularity of this contest is reflected in the number of logs and club 32 G4LAD/P ZN12 245 A 24 1.482 284 PAOGN/P 552 8 25 15 8 G4AXL/P157 entries for this year's event. What is more significant , however, is the competition, 33 G8LXV ZN12 198 A 28 1,328 205 GJ4JWA 495 which was even more intense than last year. Record club and individual scores have 34 G3W0X/A 2L59 181 A 29 1,217 301 DKOLF 497 been logged once more and this continues the trend begun when the new style con- 35 GE1YQZ ZM39 175 A 35 835 137 F6KCP 450 test was introduced. It is interesting to note that the 1976 winning club score would B 24 32 14 G W3OXD/P 200 only have achieved twenty-third place this year, and the leading individual sixty- 36 G3GJL YM60 157 A 31 1,055 212 PA3AON 440 second place in this year's contest. 37 G8TLG/P YN38 151 A 32 1,011 169 0.141CD 488 The Edgware Trophy has been won by East Bamet Amateur Radio Contest Club 38 G4AYMIP YL29 150 A 33 1,005 224 ON1RNiA 500 39 GM3PXK YP11 134 A 34 901 104 G8MFE 540 who were runners-up for the last two years. G3YDX, G3RTE, G3RPB, G3XTJ and 40 G8VYK AL34 118 A 36 791 183 F1KNO 463 G3RFS produced a fine team effort to beat last year's winning score by over 600 41 G8VGM/P 2058 104 A 39 097 103 ON5UM/A 500 points. They also provided the leading individuel score. Stockport RS "A" team were 42 G4DUR,'P 2012 103 A 39 696 110 LA3WU BOO runners-up after winning the contest for the previous three years. Gravesend ARS 43 G4KMI ZKO3 98 A 40 660 134 OKOLF 586 "A" improved upon last year's fifth position to finish third. The only club new to the 44 G8SDS/A YK38 86 A 42 580 83 F1KNO 559 top 46G8EXW/A ZM41 73A 43491 147 GJ4JWA ten this year was Maidenhead Et D ARC -A" who replace Norfolk ARC, although 360 46 GE1M0G/P AL23 70 A 44 472 82 GM8DMZ 525 the other nine clubs have all changed positions from last year. 47 GIBUPV X031 63 A 45 421 85 GM8UOM 473 Most logs were legible and well-presented, and the increased number of entrants 48 G8STO AL43 27 A 46 182 57 PA3ACIN/P 287 has reduced the number of points lost through non-confirmation of AFS. Incorrect callsigns and unmarked duplicates were the main reasons for loss of points. Contest •A - 144MHz. B -432MHz. participants are reminded yet again that unmarked duplicates attract a heavy penalty.

548 RADIO CO M MUNICA TION June 1981 A number of stations would have been placed considerably higher if they had taken Com ments from entrants suggest that the scoring requires no change but one or care in checking their logs. One word of solace to those stations, however - in next two clubs queried the necessity to exchange AFS. The HF Contests Com mittee will year's contest unmarked duplicates will attract a penalty of ten times the points claim- consider this when formulating the rules for next year's contest, which will be held on ed for the contact. 10 January 1982. G3VVPF

INDIVIDUAL SCORES

Pean Cellsign Score Society Poan Callsign Score Society Pisan CallsIgn Score Society 1 G3YDX 1.815 East Barnet 106 -I G3CCZ 955 Colchester 211 G4IMP 496 Dover 2 G3NOM 1,790 Stockpon l_G4GVR 955 Norfolk IA) _rG3ABU 490 RNARS Plymouth 212 1...GM4FVO 490 RNARS Neptune 3 G3RTE 1.720 East Bernet 106 r G2KV 945 RNARS Yeovilton 4 G3FJE 1,705 Sheflord IG3GC 945 Edgware (A) _rG3RRA 480 Farnborough (B) 214 5 G3SSO 1,690 Govt Comme (A) J-G6BCI 940 Gravesend IA) I_G4FOT 480 Bury 110 6 G3RPB 1,665 East Barnet 1.G4FIZV 940 Farnborough (A) .[G3KXT 475 Surrey 7 G4BUO/A 1,655 Gravesend (A) 112 03771. 935 RNARS HMS Mercury 216 G3LV W 475 Maidenhead (8) 8 G3PEK 1,635 Stockport IA) 113 G4ELY 930 Reading G3VYI/A 475 Addiscombe 9 G3UKS 1.630 Maidenhead IA) 114 G5CMX 925 Maidenhead CA) 219 G4GFX 470 Malvern Hills 10 G3C WI 1.615 Leicester Polytechnic (A) G3MCK 920 Echelford 220 _rG3LICZ 465 Co1chester 11 G3XTJ 1.600 East Barnet 115[G4FFD 920 Hereford 14.1 -I_G3RFJ 466 Anal 12 630AY 1,590 Bromsgrove IA) G4KPE 920 Maidenhead (A) 460 Guildford (B) 13 G3WP F 1,525 Stockport (A) 118 G4F1E 915 Leicester Polytechnic (B) 222 GG4343G 0ATwBC HYuSG 455 Themes Valley (BI 14 G4CNY 1.515 Hereford (A) 119 G3SCZ 905 Reading 455 Dover 223 15 G3101 1,505 Norfolk IA) BTO 900 RNARS HMS Mercury 455 Malvern Hills 120 16 G3I-IVX 1,500 Hereford IA) [ge.31F1M 900 Leeds G8113 455 RNARS HMS Belfast 17 G3GRS 1,490 Gravesend (A) 122 G3KJW 895 Stockport (B) 227 G3SXE 450 Cray Valley 18 G3DCV 1,485 Gravesend (A) _rG4CWH/A 885 Sutton Et Che m 228 G4KKZ 440 RNARS Culdrose 123 19 G4DRS 1,465 Shefford -LG4EVI/J 885 Wirral 229 G4KPY 435 Wirral 20 G3OHP 1,450 Gravesend (A) IG3TING 880 Maidenhead IA) 230 G3Y1G 430 RNARS HMS Belfast 125 21 G3XTT 1,430 Leicester Polytechnic (Al l_G6LX 880 Surrey 231 G3ULN 425 Plymouth 22 G3TR 1,420 Crawley (A) 127 G4GRU 870 Stockport IB) 232 G4GOP 420 Leeds 23 SG3BFP 1,405 Surrey 865 Hereford 1131 233 _rG3GM M 415 Stockport ID) rG413VVRO LG3IAS 1,405 Surrey 128 G4ARI/A Leicester Polytechnic (13) -I_GM4JCM 415 Kingsway Technical College TP 865 25 G3JEC) 1,395 Thames Valley (A) 866 Leicester 235 GI4GVS 403 East Antrim 26 G3RFS 1,390 East Barnet 131 G2FNK 860 Echelford IG3LCH 385 Sutton 8 Cheam G4DSE 1,380 Bromsgrove IA) G4BOF 855 Hereford (13) 236 G3SC W 385 Plymouth G3UFY 1,380 Addiscombe CeIGVC 855 Leicester G4C20 385 RNARS Chatham 1,375 Govt Comms (AI 239 G4JEN 370 Farnborough (8) 29 %3MZV/P 132 [G4ISKG4IAL 855 Stockport IC) 1.375 Shafford Farnborough (AI 240 G4.1BK 366 Bury 31 G3SNX 1,370 Stockport IA) 136 G3RUG 850 Stockport IC) 241 .[G 4 emJAB 355 Bury 32 G4HIU 1,335 Stockport (Al 137 G4FRN 845 RNARS HMS Belfast 355 Glenrothes 181 33 G3SOC 1,330 Leicester Polytechnic IA) 138 G3VW 835 Edgware Al( GM4JCK 355 Kingsway Technical Colege 34 1,325 Verulam IA) 1G4FAS 830 Stockport IC) 244 GM4DOK 350 RNARS Rosyth fG3JKS 139 245 jiG3H3Ru 345 Crawley Court LG4COY 1,325 Adchscombe l_G8VF 830 Eccles G m El u 36 G3GRO 1,315 Crawley (A) 141 G8SC 825 Southdown 345 Aberdeen 37 G3FXA/P 1,310 Govt Comme (Al 142 G3MGL 810 Crawley (B) 247 GM4GYR 340 Aberdeen 1,310 Guildford (A) 143 GM4GRC/A 805 Glenrothes IBI 248 fG3P2P 330 RNARS HMS Belfast 1.39 G6GS G3KKQ 1,305 Echelf ord IG4EBK 800 Grimsby IA) l_G4IUZ/A 330 Edgware 1131 144 G3RWL 1,305 Southgate LG4EOF 830 Leicester Polytechnic 250 GM3TYS/A 325 Aberdeen IG3JKF 1,300 Crawley IA) 146 ..-G4BOU 795 Verulam (Al IG4CMU 320 Sutton & Cheam 41 251 -1.G3S..1X 1,305 Addiscombe _GW3JI 795 Conway Valley 1_GM3YEIC) 320 Glenrothes 18) South Birmingham 253 G4FC0 315 South Birmingham 43 G3FYE 1,290 Stockport (B) 148 -.-G4EYD 790 IG4HKE 1,290 Hereford (Al _G318E1 790 Catterick Garrison IG74 1B/A 310 Grimsby 1131 45 G3ASR 1,285 Edgware IA) 150 G3YXX 785 Guildford (A) 254 G3RLF 310 Worcester 46 G3WY K 1.270 Maidenhead IA) 151 G4DZS 775 Thames Valley IA) G3VF8 310 Echelford rG 3ORY 1,260 Leicester Polytechnic (AI .-G2K1 770 Thames Valley IA) IG3IXC 305 Bury 47 G3PDH 1,260 Norfolk (A) 152 - G3JNB 770 Thames Valley 257 G3WFM 306 Verulam IB) 3TNO 1,260 Crawley AlI G3VVOK TIO Southdown G8AV 306 RNARS Plymouth 50 G48UX 1,245 Stockpon 4(3) »G3HTI/A 760 Grimsby (Al .-G3UVS 303 RNARS Plymouth 260 51 GIENL 1.235 Wonhing 155 - G48NT 760 Grimsby IA) ,G4IUX 303 Bromsgrove 1,230 Leicester Polytechnic (At ,_GM3PFQ 760 Glenrothes IA) 63VSU 295 Dover 52 5G3RIR 262 LG4HMS 1,230 RNARS HMS Belfast 158 GM3UM 755 RNARS Rosyth G4EGO 295 Dover 54 G4GEZ 1.225 Verulam IA) 159 G3OGY 750 Crawley Court 264 G3WP 290 RNARS Chatham 55 G3RQZ 1.220 Addiscombe 160 0480H 745 Bury 265 G4DYC 280 Norfolk (A) 56 _E ltrU 1.215 RNARS HMS Belfast 161 G3ZSF 735 Grimsby (Al fG3ZJS 275 Leicester 266 1,215 East Barnet 162 G3SVL 733 Farnborough (A) 1G4HS2 275 Leeds 58 G3BZU 1,190 RNARS HMS Mercury 163 G4OSN 715 Gravesend IB) 268 G3AHB 270 Maidenhead 18) 1,180 RNARS HMS Mercury 1G4GGV 715 Maidenhead CBI f G4E01 265 Sutton & Cheam G3JFF 269 59 [G4DUS 1,180 VeruLsm (A) 165 G3PJX 710 Guildford (A) -1.G8TB 265 Surrey 1.160 G3IOR 260 Norfolk 18/ 61 G4CAB/A Leicester Polytechnic 181 Thames Valley t8) 271 62 G4CB W 1,140 Stockport 18) 166 [G3BPMG3TAN 705 Catterick Garrison G3ZDD 260 Guildford (B) 1- 63 G2HOU 1,130 Govt Comme IA) Southdown G4JMY 250 Grimsby 181 G4BMKGM4KGJ 70505705 273 j 64 G3PRC 1,125 Plymouth 7 Aberdeen l_GM4FGD 250 RNARS Ros e 1.120 Cray Vatley 170 G3VCT 6E+5 Maidenhead I BI 275 G4HSD 240 Sutton Er Cheam G3XRX 65 IG4CWY 1,120 Leicester Canerick Garrison _FG3RBL 230 Bromsgrove (A) 276 67 G4FPH 1,115 Leicester Polytechnic (13/ 171IG G 33EFVFC 685 5a5 Maidenhead (B) -I_G4HKC 230 Colchester 68 GM4IPS 1.105 Glenrothes 1A) G4EGT 685 RNARS HMS Belfast 278 G14FUE 225 East Anirim IG3LQ1 1.100 Wonhing 174 G3PJS 693 Grimsby (81 279 G3VNG 220 RNARS Plymouth 69 G4FAD 1,100 Hereford (A) 175 G4AAL 670 Bromsgrove 290 GM4JLY 215 Aberdeen GM3YOR 1,105 Glenrothes (A) f G3KLX 655 Southdown IG4FUB 210 Verularn 181 176 281 72 G3EUE 1.090 Surrey l_GM3ZXE 665 Kingsway Technical College 1G4J01 210 Leicester 73 G3SJV 1,085 Southdown 178 G3TIE 650 Southgate IG4JKS/A 206 Verutam (B1 283 74 G3PSP 1,080 Edgware IA) 179 GM3VEY 630 Aberdeen 1_GM4CUZ 205 Kingsvvay Technical College 1,071) Crawley Court 190 G2FOS 625 Wirral 285 04/360 203 RNARS HMS Mercury 75 rG 40131. 5RS 1.070 Guildford IA) 181 G3JTG 610 Govt Comme 111) IG4CDJ 190 Reading 286 G3ASM 1,065 Catterick Garrison 182 G4KOL 605 Lovvestoh 1_GM4BKV 190 Aberdeen 77 G3VAA 1.065 Farnborough IA) _rG3KOK 600 RNARS Plymouth 288 G4KZD 185 Southgate 183 G4BVY/P 1,065 Malvern Hills LG4I0C 600 Leeds 180 RNARS HMS Belles( 289 G302Y BO G30GP 1.050 Thames Valley IA) G3WTM 595 Crawley 181 iG3YCQ 180 Echeiford 1,035 Grimsby (AI G4EC1 595 Stockport ICI 291 G2CLN 175 Bromsgrove (B) 81 83 1G3RSDG3UGK 1,035 East Barnet 185 -[G41ZB Farnborough (AI 292 G28C1 170 Ariel G3SNN 1.030 Govt Cornms IA) GM3KPD 595 595 RNARS Rosyth 293 GM4GVJ 165 RNARS Rosyth G4IRX 1,020 S('rafford 189 GM3DZB 575 Aberdeen fG3F1J 155 Colchester 294 J-G3KTZ 1,025 Southgate 570 Reading 1._G3YHM 155 VVonhrng 190 - 85 I_GM3ZSP 1,025 Glenrothes (A) G3FM W 570 Catterick Garrison 296 G3TOF 145 Leicester 1,020 Edgwans IA) 563SGQ 565 RNARS Leeds 297 GM3FRI 135 Aberdeen 87 3SHY 192 - {U4IJJ 1,020 Verulam ,G3UJX 555 Wirral 218 G4JLP 130 Shefford 89 G3T1R 1,015 Crawley (A) -G3l.MH 560 Crawley Court 299 G4IVJ 120 Bromsgrove (81 194 - 90 G3AA0 1,010 Leicester Polytechnic (Eh G4LXF 560 Stockport (C) 300 G8SM 100 Thames Valley IB) 91 G4ERT 1,000 Leicester % 3TKO 550 RNARS HMS Belfast 301 GI4K0A 95 East Antrim 196 G3J2V 990 RNARS HMS Mercury GM4EJI 550 Glenrothes 181 332 64K KO 85 Leeds 92 G3LPN 990 RNARS HMS Mercury »G3CWL 545 Sutton Er Cheam 303 G3MCX 80 Surrey 198 - G2M1 985 Cray Valley _GVV3HGL 545 Conway Valley 334 G3H1S 70 RNARS Yeovilton G3TC1D 985 Worcester -G3I3LP 535 ()unstable Downs 306 G4KTW 65 Worcester 200 94 G3YEE 985 Leeds -_G3Z0J 535 Edgware 181 306 G3JPX 50 RNARS Chatham G4EN8 985 Dunstable Downs -G3VKM/A 530 Norfolk IA) 307 GI4JXN1 40 East Antrim 202 - G6RC 985 Crawley 18) 530 Reading 308 G3NUO 30 Stockport ID) -G3AGF 975 Govt Comme 1131 204 -G4FIV 525 RNARS Culdrose 20 South Birmingham 309 fG3KKB 93 G3HAL 975 Dunstable Downs 520 Crawley (B) G4HFP 20 Bromsgrove 1E31 G3RDO 975 Crawley Court 205 Edgware (81 311 -614IR W 10 East Antrim 102 G3DOT 970 Shetford ÏGGGW3MDK4BLX3HYH 51543HYVMRD520 Conway Valley 103 G38ZR 965 Govt Comme 181 515 Leicester 208 104 IG3C0J 969 Ariel G Southgate Check logs: G3D1C. G3.1KY. G3ORH, G3VRG, G4EUP, LG5OD 960 Guildford IA) 210 GM4AGS 510 Kingsway Technical Colega G4FKS, G4JIL, G4JYH.

RA DIO CO M MU NICA TIO N June 1981 549 STATISTICS OVERSEAS SECTION 1976 1977 1978 1979 1980 1981 Posn Consign Points Penn CallsIgn Points 11 Winning club score 4,191 5,488 6,442 6,575 7,565 8,190 UR2RRJ• 364 DJ3XF 188 2 OZP.N• 363 12 OK1DEKt 184 Leading individual 3 LA2EG' 336 13 SP3FLR 172 Score 1,155 1,403 1,592 1,640 1,795 1,815 4 OK1DFF 322 14 PAODIN 79 5 DJOOE 297 15 OK2PAW 74 Number of stations 6 0828WM 282 16 U85WAL 67 scoring over 1,000 7 F8EX 269 17 SP3GVX 59 points 16 29 45 70 76 91 SP1ADM 222 18 081MSB 47 9 LA40 194 19 OL3AxN ,P 34 Number of club 10 OL488P -r 191 entries 51 51 61 77 70 74 •Cedificate winners 1-Candidates for First Time Award Number of individual entries 230 218 291 330 300 311 Check logs acknowledged with thanks from G3GC. LA6C1J, PAOCMP, LIC2 008 119 and LA9SC.

SOCIETY TOTALS 3.5MHz Field Day 1981 rules Total Total Pois Society points Posit Society points The rules for this year's contest are basically unchanged. However, the HF Contests 1 East Barnet 8,190 38 Govt Caroms 1BI 2,550 Committee is considering making the event a 3- 5/7MHz field day in future years, as it 2 Stockport (A) 7,655 39 Wirral 2,510 is believed this would go a long way towards removing the distance handicap current- 3 Gravesend (A) 7.020 40 °unstable Downs 2.495 ly experienced by entrants in the more sparsely populated areas of the British Isles. 4 Leicester Polytechnic AlI 6,865 41 Worthing 2,490 Your comments on this proposal are welcome, and should be either included with 5 Shefford 6,545 42 Sutton Er Cheam 2,403 6 Govt Comms (A) 6.535 43 Bury 2,250 this year's entry or forwarded direct to the chairman of the HF Contests Committee, 7 Hereford IA) 6,325 44 Kingsway Technical College 2,140 G3MXJ. 8 Crawley (A/ 6,310 45 RNARS Rosyth 2.115 1. The general rules for RSGB hf contests, published in the January 1981 issue of 9 Addiscombe 5.700 46 Malvern Hills 1.993 Radio Communication, will apply. 10 Maidenhead 1AI 5,625 47 Plymouth 1,935 2. Eligible entrants. RSGB members resident in the British Isles. Multi-operator 11 Verulam (Al 5,545 48 RNARS Plymouth 1.915 entries will be accepted. 12 Stockport (B) 5.440 49 Conway Valley 1.860 13 RNARS HMS Mercury 5,285 50 Colchester RA 1,805 3. Periods. 0900 1200gmt, and 1300 1600gmt on Sunday 19 July 1981. 14 Surrey 5.255 51 Hereford 113) 1.720 4. Sections. 15 Edgware IA) 5,165 52 Ariel 1,595 la) 15W dc input maximum. 16 Leicester Polytechnic 161 5,065 53 Dover YMCA 1.540 lb) 5W dc input maximum. 4.835 1.385 17 Guild-ford (Al 54 Edgware (81 5. Frequencies. 3.520-3. 570MHz. 18 Glenrothes (Al 4,795 55 Worcester 1,360 6. Contest call and exchange. Call CO FD. Exchange PST plus serial number 19 Thames Valley (Al 4.760 56 Thames Valley 161 1.260 20 Norfolk IA) 4.530 57 Grimsby I Bl 1,240 starting at 001, location (defined by place name) and county code (see Rodio Corn. 21 RNARS HMS Setae 4,525 58 Glenrothes (81 1,225 munication January 1981), 22 Leicester 4,355 59 South Birmingham 1.125 7, Scoring. 23 Farnborough (AI 4,185 60 Yeoviiton 1,015 Portable or mobile stations 15 points per OSO. 24 Bromsgrove (A) 4,170 61 RNARS Culdrose 965 Fixed stations 5 points per OSO. 25 Grimsby (A) 4,090 62 Famborough 161 850 8. Special conditions. 26 Southdown 4.040 63 Eccles 830 27 Catterick Garrison 3,815 64 East Antrim 770 la) Power. The power for all parts of the station must be derived from dry bat- 28 Crawley Court 3,700 65 RNARS Chatham 725 teries, accumulators, or "natural" sources leg solar cells or wind driven 29 Stockport (C) 3,690 66 IGuildford 161 720 generators). The practice of float charging batteries from petrol, gas or diesel 30 Southgate 3.680 i_Verulam 113) 720 driven generators is not permitted. 31 Echelford 3.575 68 Gravesend (131 715 lb) Equipment. Entrants using equipment capable of running more power than 3,180 69 Lowestoh 605 32 Leeds the specified input power for the section entered must specify how the power limit 33 Reading 3,125 70 RNARS Leeds 565 34 Crawley 16) 2.910 71 RNARS Neptune 490 was adhered to. 35 Maidenhead 161 2,840 72 Stockpot I DI 445 lc) Antennas. The maximum height must not exceed 35ft 5m) above ground 36 Aberdeen 2,595 73 Brornsgrove I 8) 315 37 Cray Valley 2,555 74 Norfolk 03) 266 9. Logs. Standard RSGB hf contest log sheets must be used with column (5) headed "Location and county code received". 10. Declaration. The log sheets must be accompanied by the standard RSGB hl First 1.8MHz Contest 1981 results contest cover/sum mary sheet with the declaration signed by the operator responsible for the contest entry. A lower level of activity coupled with poor conditions for dx working was the main 11. Address for logs. ASGO HF Contests Committee, co D. Thom, G3NKS, 37 feature of this year's contest. Scores made by the leading stations were 10 per cent Whittington Road, Cheltenham, Glos GL51 6DB. down on previous years, but the number of UK entries received was higher than last 12. Closing date for logs. Postmarked not later than the Monday 15 days after the year, no doubt helped by the introduction of the First Time Award. end of the contest. Ken Riddoch, GM3ZSP, with 52 bonus contacts to his credit emerged the winner, 13. Awards. The Houston Fergus Trophy will be awarded to the leading station in with Dennis Andrews, G3NIXJ, in second place, followed by Dave Lavvley, G4BUO. the 15W section. Certificates of merit will be sent to the first three stations in each Both second and third stations had 49 bonus contacts. In fifth place was George section. Denver, GM4IPS, who was the highest placed first time entrant. He also wins the Maitland Trophy with a total of 1,290 points in the Second 1.8MHz 1980 and First 1.8MHz Contest 1981. Winner of the Overseas section, Tom H. Kull. UR2RRJ, had 32 bonus contacts to his credit, narrowly beating Peter Woermer, OZ1W, by four 70MHz Trophy Et SWL Contest rules points. 0900 1700gmt, 16 August 1981 The following general rules, published in the January 1981 issue of Radio Cam Equipment used by the leading stations: munication, will apply: 1, 2. 3, 4e, 5a, 6a, 7a, 9, WU, 11a, 12a, 13 24. Callsign Equipment All entries and check logs to: VHF Contests Committee, c/o Mr R. Taylor, G4BEL, G M3ZSP TS520SE to invened-L antenna 12 The Rampart. Haddenham, Cambs CB6 3ST. G3MXJ SB401/S13301 to 60ft vertical and half wave dipole G4BUO/A TenTec Omni•D to inverted Ves dipole at 70ft. UR2R RJ Homebrew Is and rx to inverted Veo dipole at 170f1 DF Qualifying Event Dartford Heath rules Com ments from the logs: Calamity! RF got into the computer! G3RVVL; Operating Data: 21 June 1981. standards much improved in recent years, G31GZ Level of activity seemed lower than Map: OS Sheet 188, 1:50.000 series, Mardstone and the Weald of Kent. usual - all chasing Valentines? Good continental support saved the day, G3SJE. Assembly: 1300bst for start at 1320bst. Subject to Council approval, the Somerset Trophy will be awarded to GM3ZSP and Location: Unclassified road off A227 opposite Shipbourne Church, ngr 593 522. the Maitland Trophy will be awarded to GM4IPS. Competitors requiring tea should notify Mr C. Merry. 1 Renton Drive, Orpington, G3KKO Kent BR5 tel 0689 59381, not later than 14 June 1981.

UK SECTION Posts CallsIgn Points Posn Cellsign Points 425 1 GM3ZSP" 658 19 G3VRY 433 DF Qualifying Event Salisbury rules 2 G3MXJ• 652 20 G3JLE Date: 12 July 1981. 3 G4E1UO/A• 644 21 GM30XC 402 Map: OS Sheet 184, 1:50.000 series, Salisbury and the Plain. 39/ 4 G3XTJ 638 72 G38PM-1- Assembly: 1300bst for start at 1320bst. 391 5 GM4IPS•1- 633 23 G4AR I , A Location: Western end of Salisbury racecourse, ngr 093 285, 6 G4CP 623 24 GIN3INW Al- 383 7 G3FXI3 615 25 G3HTI 377 Competitors requiring tea are asked to notify Mr A. Newman, 74 Victoria Road, 8 G3PDL 593 26 G3UUV-I- 375 Wilton. Salisbury, Wilts SP2 ODY. tel 072 274 3837, not later than 5 July 1981. 9 G3RWL 502 27 GM4KGJt 3/3 10 G3TXF 496 28 G4ELZ-1- 342 11 G3YMC 487 29 G3SEM"f" 334 12 G4DUS 484 30 G3SXW 289 Cray Valley RS 1980 Activity Contest results 13 0357E 480 31 r.,4HSD 283 The winners and runners-up in this contest were as follows; 144MHz: single operator (16 entries) 14 G3IGZ 474 32 G4AZN 2/2 GBGGP. GBM WU and G8NN.rP: multi.operator (three entries1 G8RZP, G8SIX,P arid G8KAXiP, 15 G3SYM 4E9 33 G3FVVY 181 swl (five entries) EIRS28198, RS41733 and 8RS15.R.72. 1-8MHz: single-operator Hour entries) 16 G4FAD 458 34 G4EYO 118 G3VVVP. G37_AY and G413110; owl (three entries) BRS18529. BFIS28198 and BRS32525. 28N1Hz: 17 G4KGG-f 447 35 G3BGM 63 singleoperator lbw enure-s) G3ZAY. G3WVP and G40113: multi-operator lone entry) G3SXE: swl 18 G3LCH 436 (three entries) BRS32525, BR518529 and BR528198.

550 RADIO CO M MUNICATIO N June 1981 26 July- Anglian Mobile Rally, Stanway School, Colchester, Essex. Open Contests Calendar 10am 5pm. Talk-in on 144MHz. Further details from G3YAJ, tel 0206 39 3938,

7 June 70MHz Er SWL (Rules in May issue) 26 July- Scarborough ARS Mobile Rally, The Spa Ocean Room, The Sea Front. 13 14 June HF NFD (Rules in February issue) Open 10.45am. Talk-in on S22 and GB3NY (RB0). Refreshments, licensed bar, bring 20 June European Fraternizing OSO Party (Second) (Rules in June and buy, raffle etc. Free admission. Help available for RAIBC members wishing to at- issue) tend if contacted in advance. Details from Margaret Crofts, G4JAO, 43 Broadlands 20 21 June All Asian DX (Phone) (Rules in June issue) Drive, East Ayton, Scarborough, N. Yorks Y013 9ET, tel 0723 862638. 21 June OF Qualifying Event Dartford Heath (Rules in June issue) 27 June AGC W- DF uhf /Nib( cw (144MHz) (Rules in June issue) 2 August - RSGB National Mobile Rally, Woburn Abbey. 27 28 June Sum mer 1.8MHz (Rules in May issue) 1 July Canada (Rules in June issue) 9 August - Derby Er District ARS Mobile Rally. Lower Bemrose School, Littleover, 4 5 July VHF NFD Er SWL (Rules in Malril issue) Derby, site as previous years. All usual attractions. Details from hon sec Jenny 12 July DF Qualifying Event Salisbury (Rules in June issue) Shardlow, G4EYM, QTHR, tel Derby (03321 556875. 19 July 35 MHz Field Day (Rules in June issue) 26 July DF Qualifying Event South Manchester 16 August-Preston ARS 13th Annual Mobile Rally, Walton•le-Dale County High 2 August 144MHz GRP ft SWL School, Bamber Bridge, Preston lone mile from M6 junction 29). Talk-in on S22. 9 August DF Qualifying Event Oxford Usual attractions including bring and buy stand. Open 11am. Details from G4KMC, 11 12 August Meteor Scatter ex-GESSIV, QTHR. 16 August 70MHz Trophy Er SWL (Rules in June issue) 22 23 August All Asian DX (CW) (Rules in June issue) 30 August -Torbay ARS Mobile Rally, ITT Social Centre, Brixham Road, Paignton. 23 August DF Qualifying Event Slade Details from G2C WR, tel Paignton 558714. 30 August Ropoco 2 5 6 September SSB FD (Rules in May issue) 6 September -Vange ARS Mobile Rally, Nicholas School, Basildon, Essex. "5 6 September 144MHz Trophy & SWL 10am -5pm. 144MHz talk-in station, callsign GI34VMR. Many attractions including IARU VHF 1144MHz) trade stands, bring and buy, raffle, and refreshments. Details from Albert Smith, 20 September DF National Final Mid-Thames G4FMK. QTHR, tel 03743 3805. 26 September AGC W- OF uhf /vhf cw (144MHz) (Rules in June issue) '3 4 October RSGB UHF/SHF 13 September Telford Mobile Rally, Telford New Town Centre Malls. Shropshire. IARU UHFISHF All usual attractions plus some unique to this rally. Full catering and licensed premises October/ 432MHz Cumulatives on site. Over 50 trade stands. Further details from G8DIR, tel Shrewsbury 64273; November 1,29.6MHz Cumulatives G8UGL, tel Telford 584173; or G3UKV, tel Telford 55416, all QTHR. 11 October 21/28MHz (Phone) (Rules in May issue) 18 October 21MHz (CW) (Rules in May issue) 29 September -Peterborough Mobile Rally. New venue: Wirrina Sports Stadium. 25 October 70MHz Fixed Talk-in on vhf, uhf and hf, GB3PMR. Many facilities, plenty of free parking, overnight •8 November 144MHz (CWI caravan sites by arrangement. All the usual radio attractions in the sports hall, bring 14 15 November Second 1.8MHz and buy, bar, refreshments available. Details from D. T. Wilson, G4KS W, 4 Conway 6 December 144MHz Fixed Avenue, Peterborough, tel 76238, after 2pm and weekends. 20 March 1982 AGC W- DF uhf/vhf cw (432MHz) (Rules in June issue) 27 September -- Harlow Mobile Rally. The new venue is Harlow Sports Centre: • IARU co-ordinated date details to follow. Further information from Phil Dunbar, G8FRG, QTHR, tel 0279 39851, ext 251, office, 32486, home.

Mobile rallies calendar All information for inclusion in this column must be sent to the editor, not to Special event station RSGB HQ.

All information for inclusion in this column must be sent to the editor, not to 7 June-Hull Er OARS Mobile Rally, University of Hull Students' Union Building, RSGB HO. Cottingham Road, Hull. Opens 12am. Talk-in on S22 fm, GB3HS monitored for calls. All usual attractions including trade stands, bring and buy etc. Further details from I. B. Caress, G8EAH, 124 Dayton Road, Priory Road, Hull. Yorks. GB2CHI. 10 11 July This station will operate at the Chichester 906 Festival, in the Guildhall, Priory Park, 14 June- RNARS 21st Birthday Mobile Rally. HMS Mercury, 10am 5.30pm. There Chichester. It will operate on hl and vhf and special OSL cards will be available. will be talk•in on 432, 144 and 3.5MHz. Plenty of parking, with on•site space for in- Details from G4EHG. QTHR. valid visitors. The usual trade stands and arena events will be present. Details from G4DIU, QTHR.

14 June - Elvaston Mobile Rally, Elvaston Country Park, 5 miles south-east of Derby on 85010. Organized by the Nunsfield House ARG. Open 10am. Trade stands, displays, Post Office etc. On-site catering facilities. Grand bring and buy sale. Talk-in Looking ahead on 144 and 432MHz. Further details from I. Cage. G4CTZ, QTHR. tel Derby 103321 71875. All information for inclusion in this column must be sent to the editor, not to RSGB Ha. 21 June- Denby Dale Et OARS Rally, Shelley High School, Nr Denby Dale on the B6116, access from M1 junction 38 or 39 and M62 junction 23 or 29. Open 11 am. Talk- 21 June- ORM at the Denby Dale Mobile Rally, Shelley High School, nr Denby Dale ill on GB4CDD on S22 and GB8CDD on SU8. Trade stands, bring and buy, on the 06116. refreshments and licensed bar. Car parking and picnic area. Details from J. Clegg, G3FOH, QTHR. 12 September Scottish Amateur Radio Convention, Glenrothes.

28 June - Longleat Mobile Rally. Longleat Park, Warminster, Wilts. Talk-in on 27 September- Welsh Amateur Radio Convention, Blackwood 144MHz, callsign GB3LMR. New site closer to house. Restaurant available. Please see display ad for details of camping etc. Details from G4FRG, QTHR. 10 October- Midlands VHF Convention, Wolverhampton Polytechnic.

28 June-Rolls Royce Radio Club 03arnoldswick) Mobile Rally, Sports Er Social 11 October - El/ GI Convention, Ballymascanlon. Club, Barnoldswick. Trade stands, refreshments, bring and buy stall etc. Radio talk- in. Details from L. G. Logan, G4ILG, QTHR. 29 31 October -- Amateur Radio Retailers Association Tenth National Amateur Radio Exhibition, Donington Park, Castle Donington, Derbyshire. Please note change of 28 June- Bangor Et DABS Mobile Rally. New venue: Crawfordsburn Scout Camp, venue. Cravvfordsburn County Park, nr Bangor (Co Down). Usual attractions, bring and buy, refreshments, coastal walks, beach within I. mile. Further details tba. Enquiries to club sec Roy Evans. GI4KZN, Tel Bangor 4072.

12 July - Worcester Et District Mobile Rally, formerly Upton Rally. New venue: Droitwich High School, Droitvvich, Worcs, three miles from M5, junction 5. All the usual attractions, strawberries (weather permitting), lots of parking space, room for Amateur Radio Awards all the family. Trade and bring and buy bigger than ever. Details from Tony Blissett, G8NSL, tel Worcester 620507, or club sec Mike Tittensor, G4EKG, tel Evesham (2nd edn) 41105. This book, now revised and updated, contains details of most of the popular hf awards from all parts of the world together with details of several swl and 19 July Sussex Mobile Rally, Brighton Raceground, Racehill, Brighton, Sussex, vhf certificates. 10.30am. Special event station GB2SMR will be in operation. Many attractions in- Country, prefix and zone lists, and maps, are given where appropriate, cluding free minibus trips to Brighton beach. Free parking for 4,000 cars. Further and many photographs of certificates are included to whet the award details from A. K. Barker, 38 E(phick Road, Newhaven, Sussex BN9 9SY. hunter's appetite. 80 pages; paperback; 246 by 184m m: 1980 19 July-Cornish RAC Mobile Rally, at the Cornwall Technical College, Pool, Cam- borne. Details from 02-ABC. QTHR.

RADIO CO M MU NICA TIO N June 1981 551 Helens. For details of program me for 4, 11, 18 and 25 made on site, antenna and finance, and the group June please enquire of sec Paul Gaskell, G8PQD, tel St heard that the proposal was proceeding satisfactorily. Helens 25472. Hornsea MARS) - Wednesdays, 8pm. The Mill, Mill Thornton Cleveleys ITCARS) - Mondays, 7.30pm. House, Attic Road, Hornsea. Sec Mrs J. Heathershaw, Thornton Cleveleys Sports Centre, Victoria Road, G4CHH. On 3 April Hornsea Club entertained Scar- Cleveleys. Programme details for 1, 8, 22 and 29 June borough Club to another round of the G3GBH not available at time this entry was compiled. Enquires Memorial Trophy Quiz. After a closely fought (but to sec A. Parr, G3IWP. Slow cw transmissions on lighthearted) battle, Scarborough regained the 1-975MHz, 7pm, Tuesdays and Wednesdays. honours. The quiz was followed by a social evening at Wirral (WARS(- 3 June 1NFD planning meeting), 17 Hornsea's magnificent hq, with refreshments provided June ("Latest in electronic keyers", by G3CSGI, by the hardworking Hornsea ladies. 7.45pm. Sports & Recreational Centre, Grange Road Leeds (White Rose RS) - Wednesdays, 8pm. Moor- West, Claughton, Birkenhead. Sec Garry O'Keeffe- town Rugby Football Club, Moss Valley, Alwoodly, Leeds 17. Sec G4GDL. Club net 8pm, Thursdays, on The following is the latest information received by RRs Wilson, G8VPF, tel 051-677 1531. Wirral (WErDARC)- 10 June (Visit by G3SM M- RR 3-750MHz. The 1981 White Rose Rally was successful- from RSGB affiliated societies, clubs and groups in Region 11, 19 June (Medieval banquet at Ruthin ly held on 12 April to which amateurs (and others) time for inclusion in this issue. Basic unchanged infor- mation on other affiliated organizations will be publish- Castle), 24 June ("The visiting amateur in USA". by travelled from as far as south London. The very well- ed in the July issue. G8M M M), 8pm. Sports Concourse, West Kirby, Wir- equipped club shack is operated each Wednesday RSGB affiliated organizations are requested to report ral. Publicity secretary, J. Mills, G8NOY. evening. all programmes and news items to their regional Wineford (Mid-Cheshire ARS) - Please note that Leeds (LErDARS)- Mondays. 8pm. Old Hall Golf representatives regularly. Information for inclusion in this club has a change of venue. Meetings, 7.30pm in Club, Woodhall Lane, Calverly, Leeds. Sec G8NVP. The club now has over 120 members and a very lull the August issue should reach them by 11 June and Winsford. Visitors should contact the club secretary Rob Linton, G8XMZ, Birch Cottage, Heyrose Lane, program me, for both licensed and unlicensed for the September issue by 8 July. Club programmes are given in order of date, subject, Over Tabby, Knutsford, Cheshire. Tel Pickmere 3601 members. Pontefract IPErDARS) -Thursdays, 8pm. 11 June time and place of the meeting. All callsigns of club or obtain talk-in on S8, club net. Tuesdays, 1830. I"New equipment", by G3PSM, of SMCI, 25 June secretaries and other contacts are QTHR (correct in the This is the last entry for "Club News" to be submitted 1"2m foxhunt", by G4FP0), 9 July ("Video recorders" current RSGB Call Book) unless otherwise stated. by G3SM M. I am not seeking a further term as RR due All clubs welcome visitors and would be pleased to by G3VTO - this is a chance for G3VTD to get away for to seemingly ever-expanding personal/business/ an evening from the RAE classes). Carlton Community hear from potential new members. professional commitments. Centre, Pontefract. Details from sec G4ISU. tel I would wish to express my thanks to all amateurs, Pontefract 72784. swls, clubs, groups and others, perhaps not always Scarborough (SARS) - Mondays, 7.30pm. 8 June REGION 1-RR W. M. Furness. G3S M M, 16 Con- directly involved with amateur radio, whom I have mot INFD preparation), 15 June (NFD wash-up), 22 June iston Avenue, Sale, Cheshire M33 3GT. over the past four-and-a-half years, in Region 1 and ("G4BP over the years-, slides by G3XHA and Ainsdale (AARC) -Thursdays fortnightly, 2, 16, 30 other regions. Also RSGB HQ, and elswhere for help, G4EDR). 29 June ("Microprocessors", by G4EEV), 6 June. Ainsdale Scout HQ. Details from G2CUZ. advice, co-operation and patience given over this July lOn the air). Preparations for the rally on 26 July Bernoldswick IRolls Royce ARC) - 3 June (Official period. The many friendships made are greatly valued. are going well, and the club hopes to see many old opening of club station G3RR-operating on 144MHz I have no doubt my successor will have the same friends holidaying in Scarborough again. Scarborough fm, ssb and ht from 1900). RR Sports Et Social Club, satisfactory relationship. Cricket Club, North Marine Road, Scarborough. Sec Barnoldswick. CW classes on Mondays, 7.15pm. RAE 73s de G3SM M. G4JAQ, tel Scarborough 862638. class Thursdays, 7pm. Sec Leslie Logan, G4ILG. Wakefield (WErDRS)- 2 June (144MHz df, starting Blackburn (East Lancs ARC) -4 June (Direction REGION 2-RR D. S. Smith, G4DAX, Red Roof, at Holmfield House at 7.30pm), 16 June (On the finding contest), 7.30pm. Shadsworth Centre, Goathland, Whitby, North Yorks Y022 5AN. Tel air/natter night), 8pm. Holmfield House, Denby Dale Blackburn. Sec G8TJG. D94 786 333 Road, Wakefield. 30 June (Pitch and putt contest, Bolton (B&DARS)-3 June (Talk on the -history of Barnsley IBErDARSI- At a meeting held at I he Royal Holmfield Park, 7.30pm). Sec G4BLT, tel Wakefield radio- by G2BT01, 17 June (Club fox hunt trophy, Hotel, Barnsley, it was decided to reactivate this 255515. G8FDL Trophy), 24 June (Natter night, cw practice famous old club. Disbanded a few years ago, there are York (YARS) - Fridays, 7.30pm, except the third in etc), 8pm. Norwich Leisure Centre, Norwich, near records going back to 1913. A permanent meeting the month. United Services Club, Micklegate, York. Bolton. Sec Alan Hartley, G8PRH, tel Bolton 49023. place Is being sought, but at present meetings continue Sec Keith Cass, G3WVO. Preparations for the club's Bury (BRS)- 9 June ("Meteor scatter", by GEUHL), to be held at The Royal Hotel. Details from G4JK W, tel participation in the Great Yorkshire Show are well. 7.30pm. Informal meetings on other Tuesdays for cw Barnsley 382955. advanced. GB3GYS on stand 565 will be looking for tuition and practice, natter and noggin sessions etc. Barnsley (UK FM Group Northern) -7 June, 5 July laSOs on 14 16 July. G4lUE was presented with an in• Mosses Community Centre, Cecil Street, Bury. Full 7.30pm. The Royal Hotel, Church Street, Barnsley. scribed tray to mark his recent wedding. An exchange details of club and its activities from Chris Marcroft, Sec G8PLJ. GB3NA continues to operate satisfactori- of photographs and other momentos is taking place G4JAG, tel Rarnsbottom 2168. ly, and amateurs who would like to help support this between YARS and The York, Pennsylvania, USA Manchester (South Manchester RC)-5 June (To machine should contact sec for details of membership. Club - an interesting follow-up to QS0s. be announced), 12 June (Talk by winner of home brew Halifax (Northern Heights ARS) - 10 June 1510w' equipment competition), 19 June (Mid summer df), 26 scan tv", by G3PTLI), 24 June (Surplus equipment REGION 3-RR H. S. Pinchin, G3VPE, 61 Cole June ("432MHz linear amplifier", by Dr D. Yorke, sale 1 July (Committee ineetingl, 8 July (Visit to Bank Road, Hall Green. Birmingham 1328 8EZ. Tel G4JLG), 3 July (Preparation for VHF NFD), 8pm. Sale West Yorkshire Fire Brigade HQ- provisional, 021-TT7 1320. Moor Community Centre, Norris Road, Sale. Informal 7.45pm. Bradshaw Tavern. Bradshaw, Nr Halifax, Sec Atherstone (AARC)- 11 June ("Fast scan amateur meetings Mondays, 8pm. Sec David Holland, G3WFT, G8NUC. television", by (an Bricknell, G8KR W), 7.30pm. The tel 061-973 1837. Harrogate Repeater Group IHRG) - At a meeting on Tudor Centre, Coleshill Road, Atherstone, Sec G8SYE, St Helena (St HErDARC) -Thursdays, 7.45pm. Con- 31 March the group discussed progress of the propos- servative Association Rooms, Boundary Road, St ed 144MHz repeater for North Yorks. Decisions were tel Atherstone (0.3277) 5995. Birmingham (Midland ARS)-The club's jubilee celebrations continue this month with a cheese and wine party on 23 June when visitors will be welcome to see the new premises at 8pm. 294e Broad Street, Birm- ingham BI 2DS. Sec G8BHE, tel 021-422 9787. Birmingham (South Birmingham RS) -Thursdays YORK AMATEUR (HF night on the air), Fridays (Construction and morse classes', 7.30pm. 1 July (Surplus sale), 8pm. Hamp- RADIO SOCIETY stead House, Fairfax Road, West Heath, Birmingham 831 30Y. Sec G4GZI, tel 021-427 7104. Bromagrove IBErDARCI- Second Friday in each month, 8pm. Avoncroft Art Centre, Bromsgrove. Preparations for NFD will take place on 12 June at Stoke Prior in readiness for the next two days. 20 June (GB2BRC will be activated from Sanders Park for the carnival), 30 June (Informal gathering at the Parkgate Inn). Club net Mondays, S21, 8pm. Sec G4HFP, tel Stourport 102993) 3818, Coventry ICARS)- Fridays, 8pm. Baden Powell House, 121 St Nicholas Street, Radford, Coventry. The club now owns an FT101B for use by the members. Several members are building the club project; a variable and regulated power supply (0-15V, 5A). Sec G8SEQ, tel Coventry (0203) 598186. Hereford (HARS) - First and third Friday in each month, 8pm. Civil Defence HQ, Gaol Street, Hereford. Members will be participating in HF NFD on 13 and 14 June end there will be an informal meeting on 19 June. Sec G4CNY, tel Hereford (04321 3237. Kidderminster IKErDARC) - 23 June !Discussion on VHF NFD plans), 7 July (Informal night on the air- vhf and hf), 8pm. Aggborough Community Centre, Hoo Road, Kidderminster. Mondays (Informal), 9.30pm. Bellman's Cross, Shatterford. Sec G4ILQ, tel Kidder- Me mbers of the York ARS photographed in March minster (05621 4930.

552 RA DIO CO M MUNICATIO N June 1981 Malvern Hills (MHRAC)- 9 June (Half-hour morse class followed by a constructional competition), 7.30pm. The Foresters' Arms, Wilton Road, Barnards Green, Malvern. Sec G4BVY, 9 Wyche Road, Malvern, tel Malvern 1068451 62900. Shrewsbury (Salop ARS(-18 June (Natter night), 8pm. Albert Hotel, Smithfield Road, Shrewsbury. On 25 June the secretary will organize a country walk star- ting at 7.30pm from Pontisford Engineering works. Sec G3VWH, tel Shrewsbury (07431 51833. The Farnham VHF Group Solihull (SARS) - 16 June ("Amateur colour tele- at the RSGB National vision", by Arthur Bevington, G5KS), 7.30pm. The VHF Convention. L to r: Manor House, High Street. Solihull. Club nets G8SLE. G8TSL. baby (G3GEI). Fridays 9.30pm on 1,960kHz and (G8ZLJ), Dean, G8UVF and xyl. Thursdays, 9pm on S19 or next lowest vacant channel. G6BLU. GBYK M, Sec G4JDL, tel 021-745 3098. Morse classes available. G8V WH. G8TMO and Stourbridge (StARS1-Third Monday in each month G8HFE. Photo: G8PVZ at 7.45pm. Library, Longlands School, Brook Street, Stourbridge. A new secretary has been appointed. GEUTL, tel Lye (038482) 4019. Sutton Coldfield (SCRS) - 8 June ("Don't be bored with Baudot, or rtty is not difficult", by Jeremy Far. rance, G3KPT), 22 June ("Radio and television in- terference", by Fred Ward, G2CVVI, 7.30pm. Central Library, Sutton Coldfield. Club net Mondays, except on meeting nights, 14.5.2MHz, 8pm. Sec G8TUR, tel 021-353 2061. Ternworth (TARSI-8 June (Ten minute talks by club members), 15 June (Night on the air at the club shack), 22 June (Discussion on arrangements for VHF Melton Mowbray MARS) - 19 June (Possible meeting). Further details of events from sec S. Talbot, NFD), 29 June (Final preparations for VHF NFD), visit to Waltham tv station, contact G4ASE), 7.30pm. G8FCX, tel Litilehampton 5082. 7.30pm. White Lion, Lichfield Street, Tamworth. Club Si John Ambulance Hall, Asfordby Hill, Melton Medway (MARTS) -- Fridays. 5 June (Flea market), net Wednesdays 145-375MHz, 9pm. Sec G4FZN. tel Mowbray. Sec Richard Winters, G3NVK. tel Melton 26 June (Film), 24 July (Film). 7.30pm. The club Tarnworth (0827) 69708. Mowbray 3369. meeting place has now changed to No 1 Hall, St Lukes Wolverhampton (WARS)- 15 June ("Pre-war Horn- Nottingham (ARCON) - 4 June (Forum), 11 June Church, King William Road. Gi(lingham. RAE classes by electric trains", by Robin T. Richards, G4IRD), 22, (Junk sale). 18 June (Fox hunt) 25 June (To be an• are being run under G4HEP (chairman) and sec Peter 29 June, 6 July ("Ten metre conversion of the Liner 2", nounced). 7.30pm. Sherwood Community Centre, Poole, G4EVY. will be pleased to give further informa- by D. Dalton, G3ZLJ), 8pm. Wolverhampton Chamber Mansfield Road, Nottingham. At the recent AGM the tion on future activities. of Commerce and Industry, 93 Tettenhall Road, following officers were elected: president, G8FRB: Tunbridge Wells (West Kent ARS) - 5 June )Tour of Wolverhampton WV3 9PE. Sec G8EDG, tel chairman, G4AFJ: vice-chairman, G8RYK; sec Zone Centre telephone exchange, 8pm meet at ex- Wolverhampton (0902) 763617. G4EKW: treasurer, G4CKG. Sec Mike Shaw, G4EKW. change), 19 June (Direction finding fox hunt, starting Worcester (W&DARCI-The change of venue this Scunthorpe ISARCI -Tuesdays. 2 June (Discussion at the Drill Hall), 3 July (Junk sale), 17 July (-The year of the club rally on 12 July from Upton-on-Severn on demo stations). 7.30pm. Grange Farm Hobbies amateur's role in an emergency", by the County to Droitwich will necessitate new routines for all Centre, Franklin Close, Scunthorpe. Sec Joe Shear. Emergency Planning Officer ), 23 July (Direction finding helpers and these will be discussed at the club meeting down. G8TIY, tel Scunthorpe 732438. fox hunt, meet at the Drill Neil). Further details from on 6 July when all members are asked to attend at sec Brian Castle. G4DYF. tel Sevenoaks 107321 56708. 8pm. "Old Pheasant", New Street, Worcester, Sec G4EKG, tel Evesham (0396) 41105. REGION 6-RR F. S. G. Rose, G2DRT, 84 Cock Lane, High Wycombe, Bucks HP13 7EA. Tel Penn (049481) 4240. REGION 9-RR H. W. Leonard, G4UZ, 4 Start Bay Park. Strete, Dartmouth TQ6 ORY. Tel Stoke Aylesbury Vale (AVRSI-Future meetings every REGION 4-RR M. Shardlow. G3SZJ. 19 Portreath Fleming 505. fourth Tuesday. For time and details contact G8BOH, Drive, Derby Abbey, Derby DE3 2BJ. Tel Derby Camborne (Cornish RAC) - 4 June ("SCRs and tel 0296 64783. (0332) 556875. Chilton ( Rutherford Laboratories RC)- For meeting triacs", by Keith, G3XFL/. 2 July (Natter night, visitors Derby (DErDARSI- 3 June (Junk sale), 10 June details contact sec P. A. Braham, Building Ft18, Did' to Cornwall most welcome). 7,30pm. SWEB (Measurement evening - bring your rig along), 17 June Clubroom, Pool, Camborne. Computer section meet cot, Oxon OX1 10X. ("Aerials from the ground up", talk and demo), 24 High Wycombe (CARC)- Last Wednesday in each every second Tuesday at same place and time. Cornish June (Barbecue at Drum Hill, Little Eaton), 1 July month. Contact P. B. Shears, G4LMM, ex-G8TLK. for net weekdays on 3.714MHz at 10am and on Sundays Bring and buy sale), 7.30pm. 119 Green Lane, Derby. details. at 1 lam on 3. 692MHz. 144MHz ssb net every Sunday Sec Jenny Shardlow, G4EYM. tel Derby 556875. Maidenhead MErDARS) -16 June (Preparations for at 10.30am on 144• 275MHz except when contests are Derby (Nunsfield House ARC) - Fridays. 7.45pm. running. Details ol all activities from PRO Ron. VHF NFO), 2 July (Beginners' evening and discussion Nunsfield House, Boulton Lane, Alvaston, Derby. 14 of secondhand and surplus gear), 21 July (Evening fox- G2ABC, tel Truro 78393. June (Elvaston Castle Mobile Rally). Sec Ian Cage, Exeter (EARS) - 8 June (-Power supplies", by Alec, hunt on 144MHz), 6 August (Visit to members' G4CTZ, tel Derby 71875 or 799452. G8GON1, 7.30pm. Community Centre, St Davids Hill, Hinckley (HARAES) - 3 June )"Tachographs", by shacksl, 18 August (Talk: "Noise", by R. Hemmings, G3VCT). 7.30pm for 8pm. Red Cross Hall, The Cres- Exeter. Informal meetings on first, third and fourth G3XWDI, 17 June (Talk by G2CVVI, 27 June (GB2JCC cent, Maidenhead. Sec John Patrick, G3TVVG, tel Mondays, the Scout Hall, Okehampton Street, Exeter. at John Cleveland College Fete). Room H8G, John Boume End 106285) 25275. Details from pro Geoff Draper, 1 Carlyon Close, Cleveland College, Butt Lane, Hinckley. Sec Norman Oxford (OURS)-Contact Mark Hattam, G4KGA, Heavitree, Exeter EX1 3AZ. Geary, G8STX, tel Hinkley 632778. Exmoor (ERC) Thursdays, 7.30pm, "Loughrigg", Oriel College, for meeting details. lbstock (IARS) - 9 June (AGM), 23 June ITo be an. Reading (RARC) -25 June ("Latest techniques", by East Street, South Molton. Visits have been made to nounced), 7.30pm. The Ram Inn, High Street, lbstock. Siliconix Ltdl, 21 July ("Locator systems", by John Ilfracombe Radio Station and Bamstaple Police Sta- Sec Steve Haywood, G8UZO, tel lbstock 62158. tion. Details from Mrs Pat Jemmison. "Homedele", Morris, G4ANB), 4 August ("SWR facts and fallacies-, Louth (LEiDARC) 9 June (Visit to Grimsby College, Brayford, Nr Barnstaple. tel Brevity(' 32/ by Peter Chadwick, G3RZP). Sec Chris Young, for radar demo by G4ENE). Sec Ron Padbury G4GAB. G4CCC. Newquay (NErDARS) - 3 June ("sources - catalogues and suppliers-, a general discussion), 17 June ("Speech processors"), 7.30pm. Treviglas School, Newquay. Details from Bob Lawrence, REGION 8- RR D. N. T. Williams, G3MDO. G4LDA, 29 Greenhill Road, Wadebridge, PL27 6AY, tel Seletar, New House Lane, Thanington, Canter- Wadebridge 3649. bury, Kent, Tel 0227 66586. Saltash (SErDARC) - First and third Fridays in each Brighton (BErDRS) - 3 June (Lecture by Cmdr Hat- month, 7.30pm. Burraton Toc-H Hall. Saltash. 5 June field), 17 June ("Aerials and how to make them work", (Visit to IBA transmitting station, Caradon Hill. by Reg Varney. G5RV), 1 July (Annual evening out at Liskeard, evening), 18 July (Visit to British Telecoms at Brighton Racecourse. Food, drink and a raffle), 15 July Goonhilly. morning). Details of both trips and future (A visit by members of RAYNET), 19 July (Sussex events from Eddie Hayden, G8VVF. Mobile Rally), 29 July ("Test gear and how to use it-, Torbay (TARS) Fridays with special meeting on last by Mac, G3OEM). Further details of meetings and Saturday in each month, 7.30pm. Bath Lane, rear of 94 membership from sec J. Trimmer, G4JDM. Belgrave Road, Torquay. A party from Hameln in CaQterbury (East Kent RS)-4 June (Shack exposé). eluding DF3AZ, DJ1KR. DF4AB. DJ6WX and xyl Rosi, June ICar rally, date to be fixed), 2 July (Barbecue at DD1O W. came over to visit the club and gifts were ex. 0TH G3MD01, 19 July (Possible picnic at Ramsgate). changed between members of the Hameln-Torbay net. Pub evenings on second Thursdays in each month. Plans are well advanced for the TARS Rally to be held Dqtails of future events and membership from sec at the ITT Social Centre. Brixham Road, Paignion on 30 August. Torbay net on 3.756MHz Mondays, Chichester ICErDARC) - 2 June 'Club visit to Swan Wednesdays and Fridays at 10.30am and on Saturdays dean telephone exchange and museum), 8 June (Club at 10am. Full details from pro Les Mays. G2CWR, tel Col A. K. Haslehurst, ex-5HT, (I), presents the meeting), 7 July (Annual barbecue evening on Trundle Paignton 558714. Derby Er D ARS Founder Members Trophy to Hill, Goodwond), 10/11 July (Special events station Dennis Simms, G4FQZ, winner of the society's GB2CHI for the Chichester 906 Festival from the RR9 hopes all members will say "hello" at the Cornish annual constructors' contest Guildhall, Priory Park, Chichester', 16 July 1Club and Torbay rallies.

RADIO COM MUNICATION June 1981 553 ("144MHz transverters", by Colin Ranson, G8LBS), 1 RR19 thanks club secretaries who now read the July (Final planning for VHF Field Dayl, 8pm. Club "header" of -Club News" and write each month with Room, Rose and Crown Public House, Norwich Road. the details of lectures aimed at catching the deadline. Details from Jack Tootill, G4IFF, tel Ipswich 44047. Secretaries who send "Club News" for the current 1/singe (VARS) —Thursdays, with first meeting of the month of issue do not help that club or RR19 to com- month as regular junk sale. 11 June (Top band df pile this column. G3AAJ hunt), 18 June (HF and vhf stations on-the-air), 25 June ("Computers-, by G3XPU), 8pm, Barstable Ten. riants' Community Association, Long Riding, Basildon. REGION 20—RR B. L. Goddard, G4FRG, 2 Green. Details from Mrs D. Thompson. 10 Fearing Row, field Park, PortIshead, Bristol BS20 8NQ. Basildon. Bristol (BARC) — 2 June (Film night (ARRL and RSGB films)), 9 June (Social evening), 23 June (Computer group meeting), 30 June (VHF/NFD preparation), REGION 17—RR H. G. Cunningham, G8FG, 236 7.30pm. The University Settlement, Barton Hill, Bristol Station Road, West Moors, Wimborne, Dorset 5. Sec G8GFZ. BH22 OHZ, tel Ferndown (0202( 876018. Bristol BRSGBGI —29 June (Visit of RSGB President Fareham IFErDARC) —3 June (Measurements and Basil O'Brien, G2AMVI, 7.15pm. Queens Building, how to use test equipment), 17 June (The Bristol University. Sec G8GLQ. oscilloscope), 1 July (Propagation and Antennas), Bristol (Shirehamptonl— Fridays, 19 June (Prepara- 7.30pm. Porchester Community Centre, Room 12, Sec tion of club station for VHF NFD), 7.30pm, Twyford G4ITG. House, High Street, Shirehampton, Bristol. Sec Wyke Regis (South Dorset RS) - Following the G4GTD. AGM on 7 April the following officers of the club were Cheltenham (CARA1— Thursdays, 4 June ("The way elected: chairman, G8E0J, secretary, G3ZGP, radio used to be", by Bob Tanner, G3LRM), 19 June treasurer, G3SDO. The club now meets on the first and (Natter night). 2 July ("1980 transatlantic meteor scat. third Tuesdays each month, 7.30pm. Civilian Canteen, ter tests", by Dave Butler, G4ASR), 7.30pm. The Old Army Bridging Camp, Wyke Regis. Bakery, Chester Walk, Clarence Street, Cheltenham. Sec G4ILI. REGION 19—RR J. C. Broadbent, G3AAJ, 94 Weston-Super-Mare, RAF Locking (Royal Alr Herongate Road, Wanstead Park, London E12 Force ARS) —28 June (RAFARS at Longleat Mobile David Foster, G3KQR, winner of the 1981 Thames SEQ. Rally —skeds: daily, 3,710kHz, 1830 1900h, ssb, Valley ARTS Caernarvon Trophy for home con- G2F IX; Tuesday. 3.522kHz 1900 1300h, cwf ssb, Barking (BRES)— Thursdays, 7.30pm. 4 June (-The struction, with a trio of beautifully finished early days of amateur radio" by K. Thompson, G3ZZR/G3ZDW; Monday--Friday. 7,022 / 7,070kHz, telegraph keys all of which are in regular use on G3A MF), 11-12 July (Dagenham Town Show; a club 1230--1300h, cwissb, G8FC; Monday-Friday, the bands station will be maintained by members). Morse on 1230-1300h, 144MHz, ssb/fm, G8RAF. RAF Locking Tuesdays. Westbury Recreation Centre, Westbury will be open to the public for the Flowerdown Fair on 4 July from 1103h. G3RAF, G8RAF and G8FC will be ac- School, Ripple Road, Barking. Sec A. Sammons, REGION 10— RR P. A. Jones, G W4HAT, 68 tive on hf and vhf during the fair, and will welcome G8IZN, tel 594 2471. Pastoral Way, Tycoch, Swansea SA2 9LY. Cheshunt (CDRC)-3 June ("Components", by visitors. Sec Dave Shaw, G8RJO. Cardiff ICRSGBG) —8 June (surplus sale), 7.30pm. G8HTA), 10 June (Natter night/cw practice), 17 June The Pantmawr Inn, Pantmawr Estate, Cardiff. Further (Portable 144MHz station on Baas Hill Common (Brox- information from Joe Brooke, GVV3GHC. bourne)), 24 June (Natter night/cw), 8pm. The Church Rooms, Church Lane, Wormley, Herts. Sec Mike REGION 14— RR C. W. Tren, GM3 W0J, 21 Rich- Bragg, tel Waltham Cross 32114, or contact G30JI. mond Avenue. Dumfries DG2 7JS. Chiswick (ABCARCI— 16 June ("The station of Motherwell (Mid-Lanark ARSI) —21 June (Open GJ4GYT", described by G3GEHI, 7.30pm. The Com- day, formerly "GM3PXK Birthday Party"), lectures, mittee Room, Chiswick Town Hall, High Road, trade stands, bring Et buy, junk sales. Car parking and Chiswick. Sec G3GEH, tel 01-992 3778. refreshrnents available. Talk-in on S22 fm and via Edg ware (EDRS)— 11 June (Constructors' con- GB3CS repeater). Wrangholm Hall Community Centre, test/NFD briefing), 13- 14 June (NFD on Copthall Play- New Stevenson, Motherwell. Further details from sec ing Fields, Hendon NW4), 25 June (Summer junk GM3ULP, tel Motherwell 53394. sale/NFD VHF FD briefing). Watling Community Cen- tre, 145 Orange Hill Road, Burnt Oak, Edgware. Sec H. Drury, G4HMD, tel 01-952 6462. The Society records with regret the deaths of the REGION 16-RR M. S. Appleby, G3ZNU, 46 Cedar Southgate (SRC) — 11 June ("Tropospheric scatter following radio amateurs: Avenue, Kesgrave, Ipswich IP5 7HA. Tel Ipswich system" by Richard Dabrowski, Cable Et Wireless Ltd), (0473) 622569. second Thursday in each month. Scout Hut, Wilson Mr E. Arnold, G4JDJ Chelmsford (CARS)-2 June (Annual constructors' Street, Winchmore Hill Green, London N21. Sec Val Eric Arnold died in March. He was a whitestick competition), 7 July ("Integrated circuits for radio Austin, G8PZY, tel 01-360 est'17. communication", by P. Chadwick, G3RZP), 7.30pm. South West Harts UHF Group—The proposal for a operator, and was active on hf and on 144MHz. He was an active member of both the Brighton Er DARS and of Marconi College, Arbour Lane. Details from Andrew 1.3GHz beacon /repeater, GB3BH is expected to be West Sussex Raynet. He had been an instructor for the Mead, G4KQE, ex-G8KQE, tel Silver End 83094. passed to the Home Office among 1-3GHz Phase 1, Brighton morse class for some years. Colchester (CRAI —4 June ("Amateur microwave ac- and equipment is being gathered gradually through tivities", by Gus Coleman, G3ZEZ), 18 June donations etc. Experiments and developments con- Mr V. T. Fawcett, G3RXR ("Measurement of the thickness of plastic sheets", by tinue on GB3HR, but some problems have been ex- John Fawcett died on 16 March, aged 85. He was also G3WBM), 2 July ("Aerials for small gardens"), perienced with GB3S WH. Thanks are expressed to a whitestick operator and enjoyed the RAIBC net on 7.30pm. Colchester Institute, Sheepen Road. Details Harrow RS for generous donations to the club. More 3 5MHz . from Frank Howe, G3FIJ, tel Colchester 70189. The details from sec Trevor Groves, G4KUJ, ex G8BBE. club will also be holding another of its regular df hunts Wanstead (ELRSGBG)—Next meeting third Sunday Mr W. B. J. Hackney. G6YP on 5 Juno, 7.30pm, Fordham Heath, ngr 945 264; OS in September, after summer recess. There is, however, Bruce Hackney died on 12 April, aged 68. He was first Map Sheet 168 will be required. Details from Ian But- activity planned at VVanstead House, The Green. Lon- licensed in the 'twenties while still at school and was son, G4HKC, tel Colchester 860724. don Ell, a special event station. Details from sec R. active on the hf and 144MHz bands up to the time of Ipavvich ((RC)— 10 June (144MHz df hunt), 24 June Holmes, G3PKCL NOT QTHR, tel 556 2017. his death. He had been a member of the RSGB for the past 40 years. As a professional radio engineer until his retirement a few years ago, he was involved in the development of vhf radio for mobile communications and was responsible for the engineering of a large police radio scheme. He was a member of the Old Pat Hawker, G3VA, Timers' Club for many years. right, gave the G3PAO Memorial Lecture at the Mr C. Nash, G3BES March meeting of the Charles Nash, who died in March. was a member of the Verula m ARC to an RA)BC. audience of over 100. He is seen here presenting Mr D. Pasfield. G5NH certificates to Andy Darrel Pasfield died on 15 April. He was well known on Hope, G4INL. and Grant 7MHz during the late 'forties and early 'fifties for the Cratchley, G4ILI. of high quality of his phone transmissions. Cheltenham ARA, who were winners of both Also: sections of the Verulam Mr V. Clinch, RS43927, who died in December 1980; Contest in December. Mr G. W. Douglas, GM3N10, on 28 March; Looking on is the chairman. G3JKS Mr J. Flynn, RS38941, who died in December 1980; Mr D. J. Morgan. G4FBD, on 24 June 1980; Mr R. W. Weaver. RS43401, on 31 January; Dr R. Wynkoop, K3WY, on 12 March.

554 RA DIO CO M MUNICA TION June 1981 coil fronts, chrome brackets and dial, £15. Hygain BN86 balun, £6. G3DAM, QTHR. Icom IC255E, up/down mic, full rev/rpt, orig packing, £195. G8EPQ. 10 Stuart Close, Bletchley, Milton Keynes MK2 2NVV. Tel 0938 640249, after 6pm. FT101E, incl spare pa valves, £375. FRIO1D 160 2m, gen coy, £375. KDK FM2016E 2m fm lairs incl A/2 magnetic mount antenna by SMC, £200. All in orig packing. G4ETM, OTRA. Tel Bradford (02741 613085, after 6.30pm. FT200, FP200, vgc, manual, packing, several spare CONDITIONS OF ACCEPTANCE valves inc pa, Shure 444 mic, prefer buyer collects but would deliver 50 miles, £220. G3EJF, OTRA. Heathkit HW100, psu, 400Hz, cw filter, two-speed These subsidized flat-rate advertisements are accepted Advertisements for 27MHz equipment will not be ac- dial drive, mic, manual, spare valves, exc performance, as a service to members of the RSGB only. They must cepted. £160 ono. G3UCO, OTRA. Tel Hayle (07361 752982. be submitted on the Member's Ad form printed on the Warning. Members are advised that they should, as Liner 2, bought new 1979, no mods, £90. G3LLL rf back of a recent address label carrier used to mail Rad far as possible, ensure that the equipment they intend clipper for FT101 Mk I, 110. Shure 444 mic, high im- Corn to the advertiser: this will automatically provide to purchase is not subject to a current hire purchase pedance, £18. 2m Jaybeam Halo, £2. SMC gutter proof of membership and should not be more than two agreement. The "purchase" of goods legally owned by mount, £1.50. G3NVO. CITHR. Tel Newbury (06351 months old. No acknowledgment of receipt will be a finance company could result in the "purchaser" los- sent, and advertisements not clearly worded or punc- ing both the goods and the cash paid. 63692. Solartron double-beam scope. model CD1400 dc, tuated, or which do not comply with the conditions of The current rate is CI for 40 words or less: adver- acceptance, will be returned. No correspondence con- tisements containing more than 40 words will cost an 15MHz. vgc, £120. Telequipment S54A scope, solid- state, unused, dc 10MHz, £130. Two Philips LDL1000 cerning this service will be entered into. additional £1 for every additional 40 or less words. Each vtrs, one wkg, plus monitors, £60. Marconi TF1100 Trade or business advertisements, even from advertisement must be accompanied by the correct vvm, £60. TF867 sip gen, £20. Distortion factor meter members, will not be accepted for "Members' Ads" remittance, either as a cheque or postal order made TF142F, £25. G3MHS, QTHR. Tel 09073 73465. but should be submitted as classified or display adver- payable to Radio Society of Great Britain. TenTec Omni D, cw psu, mic. cw filter, noise blanker, tisements in the usual way. Traders who are members No guarantee of inclusion in a specific issue can be must enclose a signed declaration that the items for given, other than the first possible issue after receipt. as new, under guarantee, C725. Bearcat 220FB, scann- sale or wanted are part of, or intended for, their own Closing dates in 1981 for issues in brackets, are: 18 ing rx, 2m, 4m, 70cm, marine, aircraft, services, 20 personal amateur station. June lAugusti. 16 July ( September), 27 August (Oc- memories, £205. Yaesu XF92A 9MHz ssb filter, £15. CD44 rotator, new, £85. 2m 8-over-8 Jaybeam, £19.50. The RSGB reserves the right to refuse adver- tober), 24 September (November), 22 October tisements, and accepts no responsibility for errors or (December), 19 November [January 19821, 17 G3KLM. Tel 04867 6875. TS770, £500. Jaybeam 10XY2M, £15. MM432 /144R, omissions, or for the quality of goods offered for sale. December (February 19821. £120. FT207, no charger, £110. G8WJA, CITHR. Tel Mike, 0789 296645. Post to: ME MBERS' ADS, RSGB. 88 BROO MFIELD ROAD, CHELMSFORD, ESSEX CM1 1SS Microwave Modules M M144/28 transverter, pur- Do not post to RSGB HO or Advertising representative chased August 1980. never used, £85. TR2400, as new, under guarantee until August, E175. Both with maker's packing. Heathkit RAI cw 100kHz marker, QM16 FOR SALE £90. Heathkit 0S2 oscilloscope, £25. G4DMS. QUM. Q-multiplier, spkr, £50. G3RKC, OTRA. Tel Felixstowe Tel 0327 50632. 77208. Trio 9R59DS rx, fb cond, E55. Philips N1500 vcr, suit FRG7 rx, ssb filter, £130. Bush combined tv radio Trio TS700G, good cond, incl vox, £299. Liner 2, partly atv enthusiast, incl tapes, £100. Heathkit HW17A 2m alarm, £85. G8VHG, QTHR. Tel 0482 855436. modified, needs finishing, works ok, £65. Telequip- a.m., wkg, £25. Four-el quad, 2m, only used indoors, FTDX401, used little, mic, spkr, instruction manual, ment scope 532A, requires two valves, good tube, £7. All ono. Will accept £175 ono for lot. G4HEB, spare valves, £220 ono. 18AVTVV8 Hygain, 10/80 incl £15. IC245 gwo, £240. Tel 01-360 0210, 6 8pm. 0.THR. Tel 0287 34312. radials, £45. Two-el quad antenna, £10. G3NZY, Pre-war brands, Browns headphones. etc. Wanted: F1220 2m multi-mode tx/rx, £185. FT2 auto, 2m tx/rx, QTHR. Tel York (09041 55491. Pre-war Jones or AÑAL Handbook. Valves: 45; 81; scanning, fitted 520 23, RO, ARO, R5 6, C105. Digital Trio R1000 rx, one year old, used little, in perfect cond, 866Jr; Taylor 120 or similar. G4IMT. QTHR. Tel 500 hf tx/rx, digital display, similar FT2CO, £250. dc kit fitted, orig box, £230. Nelson, GM4IIR, QTHR. Marshfield 254. G8PCB, OTHR. Tel Wilton (0722741 3569. Tel 05552737, Pye Cambridge U1013, fitted SU20, 1464, RB14, £40. Two hf tx/rxs, Yaesu F17, 10W, one owner from FDK Multi 700E, 2m fm synth, 1 25W, immac cond, 644 Mk3, £5. Fitch 180 NAB cartridge jingle machine, new, cw, extra band xtal, 10m, £245. Matching mobile in orig packing, comp with mobile mount, manual, £100. CBM, PET, new toms, £30. 8K of dynamic ram linear, 200W pep., £85, £310 pair. Swan 350. 400W £140 ono. Telford TC7 Mk2 28 30MHz tunable i.f. with (16 x 4027), C30. Four-channel lighting sequencer, £45. p.e.p. i/p, ssb/cw, £150. G W4CAQ, QTHR. Tel Microwave Modules 2m converter, £45 ono. GM8GCY G3TGF. Tel Orpington 26802. Skewen (0792) 813239. NOT QTHR. Tel Fraserburgh 6111, after 6pm. FR101D rx analogue. lkH resolution, cw, cw-nb, am- C828M, 10W, 12 channel, manual, mobile mount, Pye PF5 uhf handheld, nicad, case, suitable for 70cm, wb, am-nb, usb, lsb, fm, amateur/broadcast bands, lighter adapter, £100, Prinz bins, 8 x 30, case, straps, £45. MM 70cm receive converter, 28MHz op, £15. 2m. 6m converters, £210. Prefer buyer ex• £8. Key 2W 2m fm tx, vca, unused, data, [23. PW 2m Creed 444 manual, £5. G8DIY NOT EITHR. Tel 0353 amines/ collects. GW8SGA. Tel Clwyd (03521 713708. rx, data, xtal tunes through 19 22, f20. G8YUE. Tel 778846. 0 M70 28MHz 70cm transverter, £50. TA33Jr, £30. 01-568 0994. 2,t/R8, all options, scanner, 25kHz/5kHz steps, etc, 70cm Tx, Pye 14460, £35. 01600 rtty modem, £25. Tulip FRG7, mint, fine tune, digital and analogue readouts, good cond, boxed, £195. G8WVV. Tel Cambridge mic, £5. 14MHz ssb Ix/ rx, £30. 70cm filter, £5. Fist mic, Joymatch 1116 tuner. £145. G8XTT. Tel Wilmington 51544, evenings. C5. 70cm 12XY, needs new driven element, £10. (Devon) 616. Trio R1000, £255. SP100 separate spkr, £18. Both G4BAD. Tel 0223 211813. Joymatch triple purpose atu, never used, mint cond, perfect, orig packing. Yaesu YH55 phones, £8. SEM Chalet bungalow, 2/3 bedrooms, gas c, h, semi- £8. G4LFG, QTHR. Tel South Shields 566658. Z-Match, £40 ono. D. Mathews, SW London. Tel detached, garage, permission granted for tower, on Yaesu FT227RA 2m memorizer tx/rx, guaranteed mint 01-876 7868. outskirts of village in north Bucks, fully furnished if cond, five months old, up 'down mic, maker's packing, Trio TS1305. 200W pep., new bands, bargain offer, desired, large rear garden, fruit trees, £Z8.500. G4EGT, handbook etc, worth £280, sell £190 ono. Cossor fm rx, E85 off list with PS30 supply. Will take reasonably uric. CITHR, Tel Milton Keynes (09081 510148 miniature valves, stalled S20 23, R3 4, exc, £20. ed piexch. Trio 2kW hf linear, offers. G4JKP, IDTHR, Som merkamp matched tx/rx. FL200B, FR100B, G3VCJ. Tel 042-43 4726. Tel Russ, Leicester (0533) 899958. good wkg order, rx modified for 160m, £150 the pair. IC260E, £275. Would consider exchange for Nascom IC255E, £195. Delivery possible en route Manchester, Will deliver reasonable distance. Roger Bryant, computer or TR7500 with cash adjustment. G4IZT, G4LAW. Tel Frank, Bristol (02721 20820, home, G3WBC, QTHR. Tel 0582 606187. QTHR. Tel Leeds 675527. 218305, work, after 15 June. National NCX5 80 10m ssb terns, some mods, Three-el beam, Hygain TH3 Mk3, balun, dismantled, DJ70S mono disc amp, 70W rms, 40, E30. C-scope KW1000 linear, 18AVT/WB, ETM3 el-bug, KW E-Zee can be viewed Newport Pagnall, hf station closed metal detector, mint, £65. Prim 240V, sec 14/2A, f2. Match. swr bridge, 30MHz 1pf, £220. May split. A. down, vhf only, buyer collects, £80. Burke, G3HEA, 12V/24V psu, 12A, unstab, £10. Amstrad 9060 cassette Mutch, Tel 0622 43443, evenings. OTHR. Tel Stevenage 4251. fm stereo, 1vvirnw 8W pichannel, £25. 5FP7 sets, tube, FT101E, cw filter, YD844A dual imp desk mic, spare TRS130 16K level 2 computer, used little, comp with £10 G4FQF, QTHR. Tel Romford 47938. unused pa valves, £380. Liner 430 70cm ssb/cw txirx, vdu, cassette recorder, few amateur programs inc), can FRDX400. exc ham bands rx, 160 2m incl 4m ssb, cw, £130. KW201 rx with calibrator, C70. Heathkit SB610 be seen wkg, £375. G4EIB, QTHR. Tel Sedgley 76131, fm. matching loudspkr, £160. Ong Vibroplex bug monitorscope, £50. All items vgc. G4IZH, QTHR, Tel after 6pm. key, perfect, £29. Other keys please enquire. Audio South Shields (06321 567780. FDK 700E, £135. IC202S MEL 25W linear and preamp, filler type PN2, peaks cw signals, kills carriers on ssb, FDK750E 2m fm/ssb, two months old, exc cond, £275 £150. All exc cond, comp handbooks, leads, orig pack- £18. G4IL W, CITHR. Tel 0632 872661. ono. 2m magnetic mount mobile antenna, as new, £13. ing, etc. G3DSV, Holmedale, Wood Lane, Morchard Two 898 Eddystone dials, Geloso vfo, all brand new, G3WUD, OTRA. Tel 01-902 7211. Bishop, Devon EX17 6PE. Tel 064-76 472, daytime. boxed, offers. G4BAB, OTHR. Tel 0533 393842. FR101DD 2 and 6m vhf bands, 20 Ilf bands, 180 10m, H W101 with Heath 403Hz cw filter. HP23B psu, Computer: TRS80 12K rom, 16K ram, manuals, level 2 12 months old, immac, Amtech 200 atu, earphones, manuals, no mods, £180 ono plus carriage at cost. Basic, comp cassettes, recorder, cost nearly E600, ab. regret selling but need the money, £450 ono. Tel 01-904 G4EBD, QTHR. Tel Watford 29696. solutely mint. £300 for quick sale. G4CGT, OTHR, Tel 9210. AREI8D, good wkg order, AR88D, wkg but needs some 0254 75037. Yaesu FC107 atu, power output, swr meters, three attention, many AR88 spare parts, BC348, perfect un- Drake TR4C W tx/rx, ac psu AC4, dc psu DC3, RV4C coaxial and single wire antenna inputs, 160 10m, six modified cond, £100 the lot. G W3DX0, QTHR. Tel remote vfo, spkr, spare valves incl pas. Drake mic, months old, boxed, as new, manual, £69. G2DHI. Tel Cardigan 10239) 710340. separate spkr in wood enclosure, ETM3C el-bug keyer, 01-727 1767, evenings. RCA ee16L rx, 80kHz-30MHz, 18 ranges, manual, the lot, £420. Reason for sale, going overseas, temp TR2300, charger, case, flexible antenna, handbook, spare valves, £75. 2m Hudson base tx with vfo, £20. OAT. G4LAC NOT QTHR. Tel 0253 729998. Lan- £170. VB2300 pa, £45. TR2300 mobile mount, C15. Two 4m three-el Vagi with balun, £12. 70cm Parabeam, cashire. TR3200, case, charger, handbook, stalled SUS, SU18, £10. Pye 4m base tx, £5. RCA diversity my rx, £10. Hygain beams: 204BA, 402BA, £75 each. You collect. SU20, RB2, RB4, £140. PS1200. £25. Servicing G3RST. Tel 089-26 2022. KW M2 mobile mount. MP1 power pack, as new, £60. manuals for TR2300, TR3200, £7.50 each. Carriage ex- FT202R. stalled S19 22, 145 6, nicads, 12V charger, Comdel processor, as new, £25. HR060 outer cabinet. tra. G8SBU, QTHR. Tel Fareham 232799.

RA DIO CO M M UNICA TION June 1981 555 loom 1C255E fm 25W tx/rx, two vfos, five memories, unmodified, Eddystone 940 spares, antennas. going for £130. Sony HP511A radiogram, pair of 10in full reverse repeater, auto toneburst, scanning and multimeter, 1400. Buyer collects. G3AJT, OTHR. Tel spkrs, exc cond. £90. Micovac model 226 test meter, standard mic, mobile mount, accessories, manual. orig Romsey 1Hants) 512557. mains driven, ex•Ministry, superb instrument, £30. Tel packing, mint cond, £225. lcorn IC215, portable fm, FRDX50, FLDX50, vgc, £310 ono. Would exchange for Bulls Green (Welwyn, Herts) 219. 3W tx/rx, channels 520 23, RO 9, PRO, R6 input, large all-mode 2m mobile tx/rx. G30YU, OTHR. Tel FT202R, S20 23, RO, R5, charger, est mic, £85. nicads, charger, case, helical and spare telescopic Lingfield 832559. FTDX560, 10-160m, CIRO, YD844 desk mic, spkr, 1p whip, exc cond, £120. Tonna 19.el 70cm antenna, in FRG7700, £268. Trio TS120V fitted with cw filter, £326. filter, manual, new pa valves, spare new driver, spare good cond, approx 5m UR67 coaxial, £13. G4JXU. Tel Trio mic MC50, £20. All ono. Gates, 16 High Mill Drive, pa valves, £230. G4DOV, OTHR. Tel Barry, Cheslyn Basingstoke 28241. Scarborough, Yorkshire Y012 6RN. Hay 109221 414927. after 6pm. FR400SDX 2m and 4m converters, manual, service Yaesu FTV250 2m transverter for 101 series, new 1981. Datong up-converter model (JCL £75. Pair new box- history, exe cond, £100. KW Viceroy 3A. ssb Is, psu, gone multimode, £99. St Barbe, G8X8 B. Tel 0462 ed Toshiba 6JS6C pa valves, £18. S. Fisher, G3Y WU, extra filter fitted, manual, £45. G3M00, Tel 021-354 813235, business, 0767 314189, home. QTHR. 9972. K W2000A 160 10m, two 6146Bs fitted for sale, digital TS452C/U, sig gen, sweep gen, 'scope combined, for FT200/FP200, all 10m, fan, 1200. Unused 6KD6, £5 readout unit (separate). 1160 ono. Icom 245E i.f, response measurement, 5 100MHz, ex-USAF, sae each. G3PJT, QTHR. Tel Comberton (022 0261 3137. muliimode, 2m, as new, £250. 4CX250B plus base and details. Jaybeam 10-el Vagi in carton, £22. Collect Must go. shack clearout: ARP; for discriminator. chimney. 110. RCA Viewlex 16mm projector, £125. Wanted: Bondis RA1B, Triplett 666H Wohmmeter, RCA S- meter, good cond, recently revalved; Slim Jim, G3W0T. Tel 0223 861029, evenings. new 6K7s, 6J7s. metal type. G3GUU, OTHR. Royd Electronics, unused; 7ERP plus cover; 65/6, orig IC240 plus Radio Communication 80-channel selector, Video cassette recorder: good home wanted for spares roc); teleprinter rolls: paper tape (at least 20 £150 ovno. FF15013 rx, £55. OM70 2m converter, 115. Philips N1500 colour vcr, plugs into tv antenna socket, reels). G4IAC, OTHR. Tel Knowle 78218. anytime Antenna tuning unit, £10. G8UC W, OTHR. Tel wkg but not very reliable, circuits. four tapes, £75. TV Trio R1000 rx, mint, latest version, dc kit fitted, £235. Bidford-on-Avon (0789881 8362, evenings. camera with UHF mod. working, £75. Buyer collects, Ken Ballance, G3KNB, QTHR. Tel 021 553 5551, days. TS1205. used little due to disability, as new. £350 or G8LRD, QTHR Wiltshire. Stafford 107851 662105, evening. offers. C. Hodgkins, G4JUX. Tel Skipton 107561 Olivetti T2CN page teleprinter, full keyboard, silence loom IC22_A, all repeaters, S19 23. PRO. R117, all 752025. cover, professional loop psu, adjusted 455BD, usual accessories. £105 ovno. Eire FM402 8.5A mains Dentron MLA250013 linear, £600. Tel 041-339 8855, manuals, perfect, £25 ono. Vintage RCA wobbulator, filters, 12 each. G3ZVVV, OTHR. Tel 01-882 5125. est 7235, weekdays, 0506 31525, weekends. Acorn valves, free to collector. Wanted: 6AS7 valve. IC215, S8 9, S19 23, RO 9, mint cond. orig packing, Trio 2200GX. immac. stalled R5 7, S20 21, nicads, G3S84, QTHR. Tel 05827 4815. etc, £95. G8VGR, QTHR. Tel 0424 429757. charger, case, strap, £95. G3CTE, GTHR. Tel KW2000 tx/rx, 10 160m, 61466 pa. exc cond, 1130. FTDX560, manual, spare valves. £150 ono. 3A variac, Sunderland 284050, after 6pm. G3ZJK, QTHR. Tel Rugby 845640. £10. Set of TCE2000 colour tv boards. £3 each EMI 13 H W8 CRP (sirs, vgc, fitted audio amp, instruction Electrovolce dynamic desk mic. HIZ, suitable for Trio, by 8 twin cone Is, £5. All items plus p Et p. G3ZNVV book, 180 ono. G4JNW, 63 Hoxton Road, Scar- Yaesu, Heathkit. etc, £20. CDE AR22 rotator, slightly NOT QTHR. Tel 01-357 3798, work, 0293 34715. home. borough, North Yorks Y012 7SX, Tel Scarborough damaged control box, suitable for uhf /vhf, multi- Trio TS7005 2m all mode tx/rx, vfo, some mats, nor (07231 69576. element beams, £25. Both plus carriage. G3JBU. mal and reverse repeater, digital frequency readout. Trio 7500 in maker's box, mobile mount, power leads, QTHR. Tel 0604 401800. £295 ono. GW4KCV, "Greenfields -, Llantwit Perdre, etc, £160. FT101B, exc cond, plastic still over front KW Vespa Mk2 power unit, handbook, four new RCA Mid-Glamorgan CF38 2HL. Tel Newtown Llantwit panel cw filter, £360 ono. Yaesu 227R fb 25kHz mod, 6LQ6, fan, no mods, 175. Trio 9R5905, stabilized etc, 10443) 202627. rev/ rep mod in daily use, r170. Tel 0656-733729. handbook, mint, 145. G3XNG NOT QTHR. Tel Hewlett Packard 175A dual beam oscilloscope, good TS770, used mainly as rx, less than 2h tx use, unmark Morpeth 106701 514574 cond. recently calibrated, comp with handbooks but cd, only packing, manual, £525, no offers. Datong asp Top band transverter. small, broad banded to suit less probes, offers. G4KOS, 310 Hagley Road, Pod speech processor, as new, 165. Deliver Manchester. FT7, FT7B or similar, with instructions, £25. Wanted: more, Stourbridge, West Midlands. Tel Hagley 882132. Travelling to London late June. GSFICG, OTHR. Tel SP901. G4H0J, OTHR. Tel 0793 771153. Trio TS.520. vgc, exc wkg order, comp with built-in do- 061-434 0434. W15FM xtals, six tx, six rx, R5R, R7. SO, S20 22, £12. do converter for 12V operation, £295. Osker block RME69 rx, 1937, with handbook, modified but Five tx plus five rx, R2 3, S20 22, C10. All above for svvri2kW power meter, exc, £25. CR100 ix, £30. restorable, £30. Kokusai 2.4kHz mech filters, HiZ WE, £20. GU3HKV, QTHR. Tel 0481-47278, 6 7pm only. G4KRG. Tel Ron, Disley 3650. 455kHz, pair, £10. G-whip, 80 10m, 125. HRO coils, Versatower P60 with post and two manual winches, FT1018 mains and 12V, cw filter, repeater xtals, fm SAE list. G3GGK, OTHR. Tel Cambridge (09541 Ham 2 rotator, approx 70ft cable, TA33JNr. approx Kent module, fan 160 10m, olio. £325. G3VI31. Oil-IR. 210374. 70f1 coaxial cable, the lot, £380 ono. Buyer inspects Tel 0405 3182. 0TH: Norfolk coast, unobstructed sea views, 60ft Ver- and collects. G4AXT, OTHR. Tel 0509 31005. Video monitor, solid-state, EMI. 14in screen, colour satower, TA33 IOXY, standing in its own grounds of SEM iambic keyer, £25. SEM twin paddle key, £15. Hi- monitor, 19in, £20. EMI studio tv camera, £99. 16rnm one acre, permission for use as guest house, seven mound HK710 marble hand key, £20. Tonna 2m nine-el lens, £9. Vidicon scan coils, £3.75, Vision mixer eight bedrooms, plus self -contained ground floor flat. portable beam, £15. Oscaramp hamgear, £12. TEAC inputs, much other tv gear. G8GOS, QTHR. Tel 0427 G3JPT. QTHR. Tel 026-370 537. A350 stereo Dolby cassette deck, photocopied manual, 3940. IC701 psu and mic, £595. IC2116, 1395. Both absolute- perfect, only packing, £50 ono. G4FKR. Tel Winchester ORT sale: Drake TR7, am/cw filters, manual, PS?, ly new and unused. S8104 and S(3604 kits, unopened, Sparsholt 557. IC202 and pa, IC224, KW Ezee Match, AR30 rotator, E-395. FT400 with cw filter, spare pas, spkr still like Transformers: various ratings, sae list Wireless 2m and 4m converters. 281V1Hz if., accu memory new, memory keyer, £29. G3RJS. Tel 01-878 5442. World, 1950 74, 180 editions, many comp years, lot, keyer, Medco lip, Datong rfcim, F1_21008. E300 FT75 80 10m ssb base/mobile tx/rx, ac and dc psus, £5. Carriage extra. G3CBU. QTHR. Tel 0256 58821. generator. G4ALG. QTHR. Tel High Wycombe 41765. mobile mount, mic, 1125. Tel Southampton 760178. Drake SSR1 rx, continuous coverage 0-5 30MHz, 30 Trio R300, exc cond, manual, rim ono. Buyer to col- TS520S. xtal filter, DSIA dc unit, mint cord, £425 bands, solid-state, manual, vgc, mains" battery, 1130. lect. 32 Lynton Gardens, Arnold, Notts Tel ono. G3XHK, 9 Wensleydale Gardens, Hampton, Mid- Carriage free. Tel 0834 3057. 0602-268794. dx TVV12 2LU. Tel 01-979 8779. PITY test sets with CRT indicators, CT473, CT490, 2m 8-el beam. £7. Pye 70cm Compact, nicads, or G3PLX/Catronics rtty vdu pcbs, major ics (program Marconi generator CT394, 10 485MHz, Solartron SU8. 135. Homebrew rotator and control, 18. 30W med 74188s, 2513, 1013, 6x21021 xtal, 140. W W syn- oscilloscopes CD1183, 10MHz, db, CD1014.3 5MHz guitar amp REOS 2N3055, £10. 34 horse motor. £10. thesized fm tx/rx, pcbs. little build, £8. Crispino db. TR408 vhf military advance audio gen, JI, offers Two morse keys, £2.50 pair. SWL vertical antenna, all, Messina, via Di Porto 10, 50058 Signa (FI), Italy. on above. Cooper, 11 Radical Ride, Wokingham, £3. Variac. £7. PW Nimbus 2m tx/rx. £45. G4KUB. Tel 2m xtals, 8MHz and 45MHz for many popular fm fre- Berks. Tel Eversley 734312. Dave. 051-924 4228. quencies, various others from 1MHz to 60MHz. SAE Microwave Modules 432/ 144 transverter (no Yaesu FT202. nicads, charger, six xtals, antennas. for list, C1.20 each. Miniature 12V relays, 2PCO, 50p repeater shift), £100 ono. G4IJ W, QTHR. Tel Bristol case, ext mic, making 1160 worth; bargain 1100. Yaesu each. Six-digit Sodeco counters, 12V coil, Et each. 621498. FT227, superb 2m tx/rx, scanning, up +down mic con- G3NGK, QTHR. Tel 01-462 2178, evenings. M B, comp with all accessories, 1300. G-whip with 40 trol, boxed, immac, cost £387 new, accept £180. Burndept 8E443 uhf tx/rx, three channels, REIO, RB2, and 20 loading coils, £20 ono. All in perfect cond. as Wanted: TR2300. Tel Sutton Courteney (023-5821 249. SU8, battery, harness, mobile adaptor incl charger, tb, new. Wanted: 2m multimode tx/rx. G3FJA, OTHR. Tel M MT432/28 transverter, £70. Electronic Develop- preamp, spare modules, manual, £120 ono. ASP 70cm Ruislip 39235. ments basic linear, fitted new 2C39. blower, antenna colinear, £12. U450L, £7. Hudson FM120 50W base M MT 144/28, mint. £70. S8 2M stalled, relay, heater, transformer, anode meter. £80. Sentinel station. 115. G8JEL. ()THR. Tel 0628 22031 144•2 14.4.4MHz, mint, £70. Nicely-made box to auto preamp, £18. M MC513/28 6m converter, £10. Sen- H W100 and power supply with built-in spkr. £130 house 640 2m amp, plus valve, 120. Various bits for psu tinel X14.4/28 converter, £12. Europa 4m transverter FT202R and YM24 spkr, mic, nicads, £60. FT2FB, for above, offers. G4HTJ, QTHR. Tel 08A92 44243. of- with cpsi, psu, and antenna relay, 150. Buyers inspect S19 24. RO 1, R5 6, 150. G31J8Z, OTHR. Tel 0202 fice hours only. and collect. G3ARU, OTHR. Tel 01-989 3196, after 421552, after 9 June. Yaesu Ff101/FP501, digital readout, 10 80m, 500W, 6pm. IC202S, three months old, rlso or exchange for good manual, packing. Shure 201 mic. exc cond. £375 ono. Late G3EDC: Heathkit works-built SB401 tx, SB303 quality hf rx, FRG7. SRX30, R1000 etc or oscilloscope. AR40 rotator, comp. £20. Telequipment D43 double rx, desk mic, handbooks, 1200 DX100U tx, £30. Would consider hf tx/rx or separates. Will beam 'scope with type A 10MHz Y amp, plug-in Yaesu FR5OB rx, £50. New and unused quad spider, deliver/collect a reasonable distance from west Cum- modules; two X10 probes, sensible offers. Low band eight 1311 Our fibreglass spreaders, hardware. 160. bria. Lafayette HA500, £30. Richardson, G8KJI. Tel Pue Vanguard AM258/Vi 1, cable, dash unit, orig mic, Mains BC221, 110. Eddystone 898, new, 18 Harrington 832127. spkr, tx, spares, £15 ono. Xtal calibrator CT432, 110 Eddystone bug, £8 W2AU baltm. new. 14. Two Offers gentlemen please: Yaesu 221R preamp, ono. Will consider part exchange for F1501 with vhf 6146A, new, £3.50 each. Will deliver Merseyside area, overhauled distributor, £315; Heathkit. pro built mobile if suitable. G411A, OTHR. Tel Mike. 05447 403, prices otherwise plus carriage. G3UJX, OTHR S8101, matching spkr, ssb/cw, 1200: AR40 rotor, 125: or 056881 326. Tel 051 677 1518. 6011 Luffing telescopic tower. Strumech, £250. Buyer FT101E, fitted cw filter. immac, 1390. FT221R, fitted TS520SE, imrnac cond, 12 months old, going inspecticollecls. G3DUF, OTHR E Devon. Tel Bill, Mutech front end, 1300. Immac TS120V. CI110. 220W homebrew QRP, orig packing, handbook, 1360 ono. 0297 gi9R•23. fin, immac, 1370. 40ft BE tower, 20h alloy scaffold G4HNF, OTHR. Tel Salisbury 6408. FT101E, unmarked cond, only packing, no mods, used tube, triband gamma matched quad, Ham 2 rotator PET 20018 old rom inpet Plessey memory expansion little, fan, mic, manual, 1350. G2KU, OTHR. Tel 01 657 switchgear. five-el XV 2m beam, cw, 100ft feeders. 1300. G3UUV. Tel 0249 2703. board, hardly used, perfect for those bigger programs, 1126. expands PET to 32K. 1150. G3XGZ NOT QTHR. Tel Yaesu YR901 cwirtty reader, hardly used. cost 1.425, a Som merkamp FL.2006 ssb/cw, a.m., 80 10m tx, Wantage 65513, daytime, 4004, evenings. bargain at 1300. Yaesu Y0901P multiscope, used little, manual, good wkg condition, £75 ono. 041YI. OTHR. Complete station of late colleague: Collins KWM24 1190. Tectronix 524AD twin beam scope, incl two type Tel Chorley 73976. FT101E. FTV250. SP100, £475. Standard C146A hand- tx/rx, tinear. 311 psu, 516F wattmeter, 302C3. TCS13 121 vvideband prearnp units, 1100. Regency digital held. C69. M M converters, 432/28S, 144/28LO, 120 transceiver. Marconi CR300 1, Storm) Viscount. flight scan aircraft band scanner, new cost was £248,

556 RADIO CO M MUNICA TION June 1981 each. L144/100W 2m pa, 190. 10XY/2M, £20. FX1 heaters, 110. Buyer collects or plus carriage. G3UOV, FT202R handheld, exc cond, xtals for R2 3, R5, R7, wavemeter, 118. E-Zee Match atu, £17.50. 13-8V psus, OTHR. Tel Crawley 883075. S20 22, comp with ext mic, mains, nicad, charger, orig £10 each. Prefer buyer collects. Tel Ma'don 10621) Yaesu FT101Z, six band model, mint cond. £400 ono. packing, extremely economical on batteries, 178. 773528, after 6pm. Yaesu desk mic, YD148 dual- Z. 112. Eddystone 940 G3ORB, QTHR. Tel Byfleet 42406. TS820DR cw filter, 1450. Drake R4B rx. £160. 30 vols gen coy communication rx with variable selectivity, Icom 720, as new, 1550. Liner 2 preamp, extra xtal, (1.97. offers. G2QT. QTHR. £140 ono. G4FAI. OTHR. Tel Bournemouth (0202) £75. Wanted: 2m multimode. G3WBN, OTHR. Tel Shack clearance: Ferrograph recorder, 3A, C10. 24848. 01-654 2761. HW7, manual, £25. BC453, 0-fivers, 13. 898 dial. Trio TS820. digital display, cw filter, ext vfo. vgc, Sony 'moot superb rx, no faults, £120. Yaesu template, £10. VCR138A plus base, £5. Heath HVV30, 1485. TR9000 2m multimode, as new, £295. Pye F460 FT202R, nicads, drop in charger, S20 22, 86, £75. two-er, manual, £15. Tel 021-354 9972. base with tit, (70cm rpir), Heathkit RFIU sig gen. 'corn IC22A, SO, S16 24, S32. slide mount, (male and Drake R4C MS4, T4XC, AC4, 0-25, 0-50, 1-5 filters, IC22A 2m fm tx/rx, p/ex gear. W H Y? G4AFY, female), £70. JVC3060 with case, £80. GM4DHJ, xtals for 29MHz cw, £480. Buyer to inspect, test and QTHR. Tel Kidderminster (0562) 63358 or 753358. QTHR. Tel 041-889 9010. collect. Heath SB301 with 2m converter, SBA3004, HQ1 miniquad, dx proven, Datong FL1 filter, both Yaesu Musen FRG7 rx, as new, used little, un- SB401, SB600 spkr, all cables and manuals, quantity vgc, any reasonable offer. G3NDO. Tel Hayling Island modified, £140 ono, or consider exchange ssb tx or spare valves, 1270. Buyer to inspect, test and collect. 5121. tx/rx. Keay, G3YX(3. 37 Leyborne Park, Kew, Surrey G3EVT, QTHR. Tel 0789-762041. Ff200. FP200, good cond, f200. Heathkit DX60 and TW9 3HB. Collins 3011 linear, plate power input, 1,000W, still HG10 vfo, 93W, 80 10m, cw/a.m. ix. £60. All with FT101EE in mint cond, orig packing. £350. FT101 the best, as new, £425. Comp set of 112 S-line xtals in manuals. Buyers collect or carriage extra. G3HAL, workshop manual, 17. Set of driver and finals, 18. holder, 170. G3UFZ, QTHR. Tel Bishop's Stortford OTHR. Tel Aylesbury 88962, after 6.30pm. Grundig stereo deck TK45, £7. Finance needed for (0279) 723088. FT101E, late model, mint, all cables, mic, manual, no micro computer project. Other ht accessories available. Pye Cambridge 2m, dash mounting tx/rx, fm/a.m, mods. orig packing, used very little, £425 ono. Dentron G4HFCL OTHR. Tel New Milton (0425) 618092. selectable via front panel switch, six channel, auto. JR -Mon 160 10m tuner, 300W rating, forward power RA117 and sob unit, £350. FT101, £270. TS700, £240. toneburst fitted, circuits, S20, S22, -133, R5, 145.8, indicator. £40 ono. D. Boniface, G3ZXX, QTHR. Tel HD mast, 40ft, £145. PF2 three channel vhf, £75. PF70 dash mounting bracket, 165. FT101E. fan, 350Hz cw Witham 518958, evenings, or Witham 517101, ext 30, three channel uhf. £85. Amtor kit, £45. Pye filter, 12/240V, mic, manual, all leads. immac cond, day. Westminster vhf, C95. All items buyer arrange swr/power meter. high power dummy load, £385. Tel CDE AR22L rotator, unused, 125. Creed 78, 120. transport. G8HVO. QTHR. Tel Pagham 5220. 0389 745126, after 6.30pm or weekends. G3ZVC module. SEI filter, £40. Parts for Thomson-CSF Yaesu FT301D, FP301D, digital 160 10m, all filters. Trio TS120V, fitted YK t.: cw filter, matching SP120 vdu terminal, 120. 48K disc Video Genie system, cost 200W. £380 ono. Yaesu FL101 tx, 160 10m, £183 ono. spkr, mic MC35S, hardly used, mint. £350. Trio over £1,000, three months old, £850. All ono. G3VVH. Yaesu XF92A, eight-pole sob filter, 9MHz centre fre- TS700S, matching SP70 spkr, mic, fb base station, Tel Farnborough (Rants) 42181, evenings. quency, £9. G3RCE, 23 Bristol Road, Southsea, Hants hardly used, £360. Electronic Developments 2m valve Yaesu FT201 tx/rx, 80 10m, 260W p.e.p., used little, PO4 9QH. linear, self-contained mains pou. 100W out, PA3 mint cond, 1235. Shure 444 mic, £15. G4HBD NOT Mutek front end board for FT221/FT225, £42. FT221R preamp, hardly used, £100. Wanted: Yaesu FT101ZD QTHR. Tel 0202 749094. multimode (2m), no mods, exc cond, £290. Case for (WARC), with fm. Yaesu FT480R, must be mint. TS700G. £300. Microwave Modules 70cm transvener IC202/1C215, £4. G8BWR, QTHR. Tel 0926 498388. Buyers test and collect or Securicor at cost. G3XIU, 28MHz if., £75. GM8BOX, ()TRW Tel 03612 2425. 14AVQ/WB. £25. Jaybeam 5XY with phasing QTHR. Tel 0946 810071, 6pm. Liner 2, pair 4CX250B, £95. New boxed Toshiba harness, E25 ono. Pye 412 mobile spkr, £8. G4FKR. Tel Quad 22 control unit and two pas, manual, £10. valves, 6JS6C. 61(06, 15each. Postage extra. Wanted.' Sparsholt (Winchester) 557. Z-Match, £5. Cowlgill, 13. Sesyns 50V, 3in, £5 pair. 12AV0 antenna or ATV3. GW3EJR, OTHR. Tel 0239 TS520. cw filter, VF0520, SP520, all in fine cond, 144MHz 6-over-6 slot, £4. Miscellany power supply 2331. comp with orig packing, manual, accessories, buyer units, Walter air/sea rescue txs, miscellany valves, incl Heathkit V7AU valve voltmeter, first class cond, collects, £385 ono. G3IMK, QTHR. Tel 01-397 6924. PT15s, 807, EF50, etc. G2CMK, OTHR. Tel Norwich leads. handbook. £12. Datong Electronics Ltd vil con- TS520, VF0520, cw filter, 250 ac, 12V de supplies, 45457. verter, 0 600kHz, new, data, circuit, £10. Both plus mint cond, orig packing, manual, buyer collects, £390 Datong morse tutor D70, only six months old, pass- post. G3ISP, QTHR. Tel 0632-837401, after 6pm. ono. G3B11, OTHR. ed GPO test first time! Comp with earpiece, key plug, loom IC251E, £345. Stolle automatic rotator, align- Trio R1000 ht communications rx, immac cond, used in orig packing, £40. Tel Swindon (0793) 782787, even- ment bearing, 23m control cable, 140. Eight-el Yagi, little, boxed, £230 ono. Scrase, "Marsden", Pon- ings. 25m UR67. £15. Packer wavemeter, £8. FDK Palm 4, patrick. Wigtownshire. Tel 077-681 258. New boxed NR56 2m rx, 135. HW8 with rit neatly fit- 165. 5/8 2m mobile whip and mag mount, 110. FT101, 1974, as new, no leads or accessories, belonged ted, unmodified front panel also available, £50. Richardson. G8UVC NOT QTHR. Tel Aylesbury (0296) to late G6CU. Best offer secures. Tel Christchurch Stereocode adapter in West Hyde case, 15. Used 81:0:1. (Dorset) 0425 72441. vidicons, £2 each plus postage. G3IRM, OTHR. Tel Standard C146A charger, helical, 175. Starfone FDK Multi Palm sizer, 2m/fm. 40 channel handheld, 0284 4318. charger, spare battery, 150. SBE uhf scanning rx, £35. external spkr, mic, 1120 ono. G4FUB, QTHR. Tel Programmable calculator, SR56, 10 addressable Eddystone EC10 rx, £40. MM converter 144/4-6, 115. Hemel Hempstead 41921. memories. 100 program steps, rechargeable batteries, 70cm converter, !Fa-6, 110. Varactor tripler. 120. Microwave Modules MML144/100 100W 2m pa, mains adaptor, handbook, case, £25 ono. GBALR, Wanted: Icom IC3PA power supply. G8CJM, OTHR. £100. MMA144V auto switching preamp, £24. QTHR. Tel 0264 3741, evenings. Tel Medway 47280. MMT70/144 4m transverter, £80. TR9000 accessories: ZX80 microcomputer with pou, leads and basic pro- Yaesu FTZZ7R, 2m, fitted scanner, as new, €175. B09 base unit, £22. SP120 spkr, £18. G4BWB, OTHR. gramming manual, Sinclair tested in 1981. £65. G8YZS, Mirage vhf 80W linear, new, 195. KW109 super match Tel Bristol (0272) 426486, after 6pm. 177 Fairlee Road, Newport, loW PD30 2EW. CtRO atu, £85. KP12A speech processor. £20. Large FT101B, 350Hz cw filter, unused, spare pa valves, all Uniden 2030 2m fm, 195. Eddystone 880/2, superb 111 quantity OST, CO, 73, Horn Radio magazines. Drake leads, mic, manual, vgc, £330. Straight key, £3. fX. 1175 ono. Hallicraf ters 5X62 230 ac. €55. Marine TR7, PS7, RV7, MS7, FA7. NB7, SP75, etc, all filters, Homebrew cmos touch paddles, 14. Jap mechanical vhf txirx, 175. AR88LF, 125. Nems Clark 50/250MHz manual, as new, boxed, cost near 11.700, snip £1,100. bug key, 14. Carriage extra. Fraser, G4BJM, QTHR. tunable rx, 175. Valve tester, £5. SAE list. Cain, 18 Drake R4C, blanker etc, exc, £295. Yaesu FL2100B Tel 0908 653961, work, 0908 72483, home. Oaky Balks, Alnwick, Northumberland. linear, as new, 1250. Jim Taylor. 5 Luther Road, Win- FT200. FP200, average cond, £195 ono. G4ADE NOT Trio JR310 amateur bands communications rx, ton, Bournemouth. Tel 510400. OTHR. Tel 04012-4365. 160 10m, selectable usb, lsb, a.m., wide, narrow filter, Liner 2, preamp, Pye mic, £85. Bellsonic pou, 3A, Liner 2. preamp, piptone, manual, mobile bracket, Pye 180 ono. Trio 2303, as new, helical whip, orig packing 13-8V, 18. WM2 wavemeter, 110. Jaybeam four-el mic, pou. £90. QC:n/0640A linear, pou, £20. Uniden etc, 10 months old, used little, £135 ono. G4ENG, quad, 110. Stolle 2050 rotator. £20. Prefer buyer col- 2030 (2m fm 12 channel) toneburst, manual, mobile OTHR. Tel Cheslyn Hay 417477. lects. G4LSW, ex-G8TNR. Tel Bedford 781323. bracket, €90. G4LBH, ex-G8KYU, QTHR. Tel Luton FRDX500, FLDX500, vgc, serviced, new valves, £290 FT101ZD„ incl fan, spare 6146Bs, £500 ono. FL21006 415846. ono. HF5 vertical, radial system, 145. Will exchange for linear, £260. Both in mint cond. Heathkit power meter KW2000, exc cond, incl mains psu, £160. FT207, mint good 2m rig, G4LJG. ex-G8SUL, QTHR. Tel 09334 HM102, 130. Two Yaesu SP101 spkrs, £10 each. Two cond, cw, two nicads, charger, £160. German wartime 53990, evenings or weekends. Toshiba 6JS6C valves, one 12BY7A, 112 set. G3MSL, rd l bridge, by Siemens/Halske, offers. Tel 0788 72219. TW 2m Nuvistor converter, 28MHz i.f., (5. 3cro high- QTH R. Tel Fleet 21446, after 7pm. G30110, OTHR. () cavity wavemeter, with micrometer screw, 17. 21in TR2300, helical, nicads, charger, £125. Multi U11 70cm FT1012 160 10m, ssb/cw, fan, solid-state, 2 x 6146B dish, £3. Buyer collects. G4B WW. OTHR. Tel mobile, fitted 13 channels, 1145. FT101E hf tx/rx, C325. pa, rf speech processor, variable if. width, noise Southport 10704) 29036. MMT 432/28S 70cm transverter, £85. Radio blanker, in-itt vox, exc cw envelope shape, h/book, Bargain: Trio TR2300, boxed, comp with nicads. Communication Handbook, fifth edition Vol 1, CS; Vol £375. Sell due change of plans. Must collect. Tel charger and helical, £150 ono. Ayo CT38 electronic 2, 14.50. Buyer collects. G8KMV. QTHR. Tel 0438 01-640 6020, daytime. multimeter, scrap unit for spares. £25. Hewlett Packard 54689. MR1000A 2m scanning rx, scan or manual tune on microwave power meter (no information', 115. Microwave Modules MMT144/213 transverter, £75. selected xtal controlled channels. R2, R7, S20 -22 in- G8KXM, QTHR. Tel Stoke-on-Trent (0782) 535316, 144 28 converter, 118. 1,296 28 converter. 123. cluded, as new, comp with nicads, charger, orig pack- after 7pm. 1,296MHz varactor tripler, £23. All incl p/p. Gone ing, £30. Tel 01-472 7272. Marconi sig gen TF995/A5, a.m./fm, 220MHz, exc multimode. G8OUV, QTHR. Drake R4C with MS4 spkr, noise blanker, £250. T4X8 cond, manual, adaptors, recently overhauled, Trio 7200G 2m fm bunt, not used mobile, fitted 13 with power supply, mic, 1190. Both exc cond, space calibrated, £225 ono. Airmec a.m./fm mod meter, channels, mobile mount, manual, perfect cond, un- for new bands. Wanted: Yaesu vfo FV101 series. 300MHz, likewise. 1125 ono. Bird 43 wattmeter, as used 2m mobile whip. base, £110. Buyer collects. G3VLX. QTHR. Tel 0689 26584. new, 50W 100 250MHz, 1100. 600MHz counter, [103, G3KZU, OTHR. Tel Oxford (0865) 63000. ASCII keyboard, Keytronic. top commercial quality, 5A pou, 140. GM4FDM, OTHR. Tel 0505 22749. KW2000B, new pa, good cond, £220. Buyer inspects, parallel output, current production cost 1101, unused, Labgear 160 twin mobile, £20. Labgear 12V dc power collects. G4FZK, OTHR. Tel Melbourne 2687. £35. Micro bits, all new: 8255s, £2; 825s, £2; 9212s, £1; pack, £15. Medium wave 160m converter, £6. 160m Video monitor, Hitachi 12in professional model, ideal 8085, 11; 2102s, f1; TIL311 hex, displays. 13; 1MHz loading coil, whip, 15. Collectors 58 set 1943. G3MB W, for rtty, fstv or micro computer, brand new, boxed, stals, 11. G3XSJ NOT OTHR. Tel Bristol 685280. OTHR. Tel 0943 74794. 1175. Oscilloscope. Solartron CD1740 dual beam, DC- Exchange for Ix/ rx or radio gear: Scarce collection of KW2000E with psu, exc cond. 160 •10m, 2 . 614Bs 50MHz. 1495 ono. Drake R7!TR7 tx/rx interface cable Cape of Good Hope stamps, SG cat value 14,000 and final, all usual functions plus KW110 Q-mult, 1290. kit, 115 ono. PL259 plugs, elbows, sockets, any 50p. will increase in value, offers. G2MF. OTHR. Tel Shef- Buyer to inspect and collect. G4GCJ NOT QTHR. Tel Tel 0602 54047. field 360210. Milton Keynes (0908) 644253, evenings only. FT75B tx/rx, ac peu, vio, exc cond, 12AVQ ant, never FDK TM5613 2m rx, vgc, £60. KW E-Zee Match atu, Telescopic tower W40. three 14ft sections, 1145. used, 1150 ono. Buyer collects. Dr Jaggarao, G4BVL, vgc, 130. Wanted.' AR88D for rebuild. P. M. Cleaver, Three-el 4m Jaybeam. 15. BC221 with charts, stabiliz- Royal Sussex County Hospital, Brighton. Tel 86 Main Road, Dovercourt, Essex. Tel Harwich 2195. ed psu, 112. Meaty transformer, 615 0 615V, 625mA, 0273-606611, after 8pm. Trio T599S is, matching rx 85990, £350. Prefer not to

RADIO COM MUNICATION June 1981 557 split. Trio TR7010, £90. Mizuho SB2M, £90. All ovno. Trio R1000, as new, £240. Decca Supermatch KW109, sig gen. Need servicing manuals or circuits for both. Is Buyers collect. G3YEU NOT QTHR. Tel Cheltenham £99. Datong multimode audio filter, £80. All in perfect anyone willing to loan for short period or sell. G4GSC, 511187. cond, matched pair of 6K06 valves, new. £7. BC221 OTHR. Tel Staines 51898. Yaesu FI7 hf tx/tx, never used mobile, extra coverage frequency set, power pack, charts, £22. G412G, OTHR. Ham marlund HQ180A manual. G4BDQ, OTHR on 10m, 28 29MHz, E240. G4HSY, OTHR. Tel Tel 0903 41109. Southampton. Shoreham (Sussex) 4631. Cossor dual trace scope, 5MHz min circuit diagram, Feedthrough capacitors, 1,000pF, 350 500V vvkg, KW2000E ac psu, spkr, dc psu, atu (160-10), trap spare new tube, £40. 0M70 high power, 28 144MHz bolt-on type for aluminium chassis, 36. or as many as dipole, balun, feeder, svvr meter, hand mic, morse key, transverter, wired for FT101 /200, £65. TDZ a.m, rx, possible. Split stator 16 16pF or 25 25pF ceramic leads, manual, orig packing, all new except lxirx, needs alignment, [7.50. G4IDF, OTHR. Tel Worcester capacitor with wide vane spacing for valve tx output. which is in fine cond, lot for £375. G4DC W NOT 20135, after 6pm, R. Coleman. Tel Upminster 186) 21523, evenings. OTHR. Tel 0274 684377. R820, the ultimate rx, transceives with TS820S. vfos Circuit diagram of calibrator, xtal No 10, ZA32171. A. FT200, FP200. used very little, in orig boxes, DX with TS520, still under guarantee October 1980, £625 R. Bartle, 105 Mayfield Road, Thornton Heath, Surrey. listings, US listings, 1980, £185. Buyer collects. Tel ono. TS820, perfect, about 18 months old, used little, Tel 01-684 0610. Richard, Brecon 4368, anytime. desk mic, £575. G4GEZ. Tel Roger, Luton 38866. To buy or loan: manual for 031 scope or will ex- Digital frequency counter FC5M, 50MHz, five-digit Som merkamp TS310DX 10m fb rig, worked VK change manual for S31 scope. Tel 03542 3181. led display, minus 455kHz offset, 12V or 5V dc supply, E120. FRG7000, mint, E195. Brand new, Software for research machines, 380Z, rtty, cw, sstv. E.25. Tel Carnoustie 52813. unused Bird Termaline power meter, 1-5118A/ AP etc. W H Y? Whatton, G4DCV, 199 Gladstone Road, TR7500 fm tx/rx, all channels, easy op mobile, exc 20MHz 1.4GHz, 500VV, £95. Airmec 210A modulation Weimer, Deal, Kent CT14 7EL. Tel 0304 840671, ext 56, cond, all accessories, £150. Heath SVV717G rx, £30. All meter, am/fm 3-300MHz, E70. Pye Olympic 12 chan- office hours. ono. G8IMT, QTHR. nels, unmodified. Mains psu only. Suitable for KVV2000A with two FDK2700 MIc2, all mode 2m synth and vio. 240/12V Nineteen-inch rack on castors, remote pan and tilt 6146, commercial or homebrew, for a KW2000CA on Oscar converter, speech processor, no mods, hand• head, rtty station, picture and waveform monitor. mission in Zaire, 80 to 103°F. Details please to G3TWS, book, service manual supplied, all orig accessories, Another monitor. 2m tx / Tx. Offers. Tel 01 352 1412. 32 Bibury Road, Benhall, Cheltenham. Glos GL51 68A, £300 ono. BLW60, 45W at 2m. new, £5. G8RZC, Tel 0242 22366. QTHR. Tel Newmarket 5783. Gen co+, rx, older type: Eddystone 640, CR103 or FT101 Mk1 with160m, rx ok but no pa valves, tx requir- W ANTED similar. G4FIL.I. CITHR. Tel Blackpool 10253) 729718, ing attention, £150 ono. G3LLL fm unit for FT101, E22. G3AAG would welcome advice from another G station evening, 733910, daytime. Drake R4A, offers. G3XTT, QTHR. Tel 0604-37894, who has recently operated with reciprocal licence in PDP8A 4/20BN, comp or boards. KK8A, MM8AA. after 6.30pm. Kenya. Safari planned next October. Also UK sked re- MM8AB, KM8A, KC8AA, DKC8AA. GI3KYP. CITHR. FT101E with cw filter, £100. Kent FM101 fm rx;tx unit, quired. V. Copley-May, Flat 21, 17 Clarges Street, Lon- Tel Belfast 6renn, evenings. £55. Europa C transverter with repeater shift, spare don W1Y 7PG. Manuals or circuits for: Cossor tx 12m), C22 PB6 or valves, E70. All three together, £510. Trio 9R59DS Tx, 18AV Q vertical ant, KW E-Zee Match. Trap dipole. similar. Sig gen and scope by Airmec. Radnet type 211. £45. Prefer buyers collect, all exc cond. G8CHK. G3RST. Tel 089-26 2022. Documents returned promptly and/or all costs of Northants, Tel 0327 830788. Exchange antique guns or good English shotguns for photostats and postage paid. G4IYI, 16 Casterton, TR9000 multimode, used only for base station, six modern Drake or Collins ht rig. Tel 021-556 1322. Euston, Chorley PR? 6HN. Tel Chorley 73976. months old, comp with all accessories, mobile mount business hours, for details. Drake R4 or 28. G5LH, OTHR. Tel Newcastle 662490. unused, manual, orig packing, as new, going hi, £295. 82 suitcase set or any other wartime suitcase/spy type Robot model 80A slow scan tv camera. GM4DAE, Datong morse tutor. £30. G4KE W, 60 Drake Road, radio. Any cond or incomplete welcome. G8VDZ, QTHR. Tel 041-778 5040. Harrow, Middx. Tel 01-868 8368. QTHR. Tel 01-949 2317. Racal rx accessories and Racal books. MA35013 syn- FT2F 10W 2m mobile ta/tx. RO, ROT, R3 6, R6T, R7, Information low frequency rxs loop antennas. For- thesizer, MA1210 Racalator, MA168 diversity switch, S20 23, new i.f, filter mounting bracket, mic, £75. mulas construction tips particularly for BBC4 200kHz in comparator, oscillator, converter, preselector. John G3VPX. Tel Sheffield 874324. south Spain. Ian Millar. Urb, Los Argos. 10 La Nucia. Porep, 050VB, Larchmont, Ladygate Lane, Ruislip, R1000 rx, as new, £235. G3TCU, OTHR. Tel Guildford Alicante, Spain. Middx HA4 7C1R. 10483) 65607. Icom ICR M2 or RM3 for IC211. For sale: M MT144/28 Pye Bantam hi-band a.m. Nicads, cases, mica, good Yaesu FR6OB rx, top band, xtal cal, attenuator, exc transverter, as new, G4H W, OTHR. Tel 07956 2782, prices paid. Any cond considered. G2AFD, QTHR. Tel cond, £75. 5 Bridge Road, Oldfield Park, Bath. Tel day. 0795 872157, evenings. Malvern (068451 3242. Mark, 24068, after 5prn. Monoscope tubes for my working museum. KW107 att.', must be good cond. Stobbs, G8YGU, 78 4m sale: Cambridge, 70.26 , AM10 boot, six chan- Reasonable prices paid. G8PTH, QTHR. Hershel' Drive, Middlesbrough, Cleveland, Tel 0642 nels, xtals, fittings, manual, £35. AM U) dash, xtals, Instruction manual and circuit for Trio 2200GX to 211685. bracket, £38. Ultra 486 handheld, nicad, xtal, £25. £89 borrow or copy. VF030G, state price. G4KZE, 18 Lor- Transformer for KVV20008 txirx psu or psu for same. for lot or offers. G3SLI, OTHR. Tel Reading 479850. raine Road, Timperley, Cheshire WA15 7NA. Tel Low Z headphones, mono. G4AKX, OTHR. Tel Trio TV502 2m transverter, ssb, cw, to match TS520 061-980 4195. Nor thwich 76538. etc, manual, package, £85. G6AS, QTHR. Tel 021-706 Handbooks for Ayo valve tester, MN6M/ 504 vec- Still required: ARRL Radio Handbook before 1936 3709. torscope, Dynamco scope 07100 + 1 2 TB 1- 1Y4 and 6V Mallory Vibropack, 125V or near output. Alad- Samson ETM 3c keyer, new, boxed. £48. Eddystone IY2 Y amp, Marconi auto-slide changer 6228. 10in din ift type A or G and Hammarlund ceramic us valve S-meter, table-top mounted, instructions, £7. Acos diameter roof extract fans (Ventaxia). Real money paid. holder, with suitable coil formers. G4IMT, CITHR. Tel type 40 xtal mic, £3. All post paid. G2BGG, QTHR. Tel G8GQS. Tel 0427 3940. Marshfield 254. 061-427 1903. Circuits/manuals for purchase or loan for photocopy- Variable capacitors. wide-spaced 2000F and split Eddystone 680X rx, gen coy, 480kHz--30MHz, xtal ing on Pye Vanguard AM2513, Any conversion to fm in- stator 150 + 150 pF or near values. GM2T W, QTHR. phasing, 15 valves, no mods, £90. Trio 2200GX. 12 fo appreciated. All costs reimbursed. Owen English. Xtals type FT243 (unm odified) in range 7,000 to channels, new nicads, charger, case, dial light, £95. G4HST, c/o Oldchurch Hospital, Romford RM7 OBE. 7,040kHz and 3,500 to 3,600kHz. Please quote fre- Both good cond. Four SK600 bases with chimneys, £6 C W tx or tx/tx, H W8 or higher power, hf bands. quency and price. GM4FDD, 95 Morningside Avenue, each. Suitable blower, £6. Taylor, G4EBT. Tel G3ASE, QTHR. Tel 0480 63129. Aberdeen AB I 7NU. Rotherham 70021. Wilcox-Gay oscillator. 237 Colmare Road, Lon- Heathkit HVV8 and psu, HIN] considered, good price Capacitors: Sprague Electrolytics 330,000eF (5V), donderry. Tel 0504 51973, evenings, 0504 43457, paid if mint. Codar AT5. Write before July, Nelson, 66,000 (30V), 51,000 (15V), 47,000 17-5V), 40,000uF daytime. Apartado 912, Barcelona, Spain. July onwards, Flat 140), large stock, computer grade, £2.50 each plus Heath SB644A remote vfo. Heath SBA3012 400Hz 27, Fratton Buildings, Fratton, Portsmouth, Hants. p&p, clamps free. S/mica 43pF and 160pF t3F. 500V xtal filter for HW101. Heath SB620 spectrum analyser. 240V, 800 1,000W alternator. Do not want comp 68.14F. 35V (Ely), both 20 for 20p. All components new, Steve Pocock. G4GTU, OTHR. Tel Rustington (W generator unless cheap. CDE Ham 4 rotator. Blake, sae for enquiries. Mike Thomson, GM4JEJ, 1 Osborne Sussex), 4123, Cedar End, Carleen, Bre,age, Nr Helston, Comvvall Terrace, Arbroath, 632A Telequipment Serviscope, tech model TE2OD TRI3 90P.

SEE THE RSGB MAIL-ORDER PRICE LIST WE ARE THE ON PAGE 584 MOSLEY ANTENNA PEOPLE Mustang 3 elements. 10, 15 and 20 metres £146.03 TA-33 Jr. High Power model incl. Bales 3 elements, 10, 15 and 20 metres (132.00 TA-33 Jr. 3 elements. 10, 15 end 20 metres. £118.00 MODULAR ELECTRONICS 95 He St, Seksey, W. Sussex P020 OOL Selsey 102436112916 TA32 Jr. 2 elements. 10. 15 and 20 metres £78.00 s.s. M. RF Power Transistors, Specialist RF components. Low noise Devices. TA31 Jr. Rotary dipole, 10. 15 and 20 metres m ix 2N3866 98p. 2N4427 £1.08. 2freA3 £1.17. 2N5913 £1.81. 2N6080 £4.72. 2N6081 17.94. 2N6082 ELAN 3 elements, 10 and 15 metres 193.00 £1.63. 2N6084 112.86. 2N5590 £6.33. 2N559 I 17.94. 2N5944 £6.79. 2N5945 £3.63. 2N5946 TD-2 Trap Dipole 40 and 80 metres £40.00 £10.63. 2115914 £4.60. S01127 12.42. S01143 £6.90. SD1416 £24.15. S01019 £18.40. sr:n .135 TD-3 Jr. Trap Dipole 10. 15 and 20 metres POA E5.20. SD11313 f7.77. S01088 (18.40. S01089 £25.30. SC11434 128.46. 5D1477 f28.76. SD TCD-2 Trap Diode 40 and 80 metres compressed (50.00 Devices cover 4 to 100w out. Ex Equip RF. 2145070 £2.50. 2N3632 f2.50. Low noise Small Signal V-3 Jr. Trap Vertical 10, 15 and 20 metres £36.00 BFR90 11.82. B FR91 £3.46. BFR34a £2.25. TP491 £3.68. 40673 92p. 3N204 £1.55. BF903 11.30. Atlas Trap Vertical, 10, 15, 20 and 40 metres 160.00 EiFY90 (1.15. BFT66 12.59. SD291 (2.46. S0306 (2.60. 2N918 60p. 2N5179 82p. 13F115 50p. SWL-7 Dipole 11, 13, 16, 19. 25, 31 and 49 metres £36.00 RD-6 £*.00 811813 50p. ST2110 - 2N2369/ SX2030p. ZS276 1.5a 600e 12p. 400v 2.5aBr 50p, H.P. Diodes Dipole 10, 15, 20, 40 and BO metres 5082.2800E1.10, 2835 96p. 3010 98p. Ant Relays 12v 18.57. PTFE Sheet 30cm Sq 12.30. X(1 Fill Orblt Venice) 11, 13, 16, 19. 25. 31 and 49 metres £56.00 10.7MHz 25kHz 18.06, Trimmers. Seder 10pf 33p. PTFE Film 9pf or 18pf 28p. 25p1 15p. BNC Plug 709. BNC S/H sock 899. 4h Sock 63p. 600MHz - 101.c. MC12013p 111.50. BF9C0preamp Administrative Address on)y (Al) antennas available ex works, carriage and VAT extra) 11441 £8.06. BFR34a pre/a 1432/ (1.62. Ferrites FX1115 8p. FX1898 139. FX2049 12p. Heatsmk 6M1 6' 11.90, 4' £1.26. TBA120 I.F 1/C 62p. Modules. RF Amp with CO. CPM15-2 M O SLEY ELE CTR O NIC S LIMITE D 1.5w 15w £27.03. CPM25-3 3w . 20w F28.46. Send for details. RF amps 50 in/Out no C/0. 196 Norwich Road, Ne w Costessey, Norwich NR5 OEX PM2-10 0.4w 10w 118.50, PM2-15 1.5w - 15w £19.60. PM2-25 3w - 20w (21.00. RF Amps 50 in/out no C/O. PM70.10 1.7w lOw 1432) 121.50. PM70-4 0-4w - 4w £19.60. Send for HANDBOOK contatrang full range of Antennas and technlcal information, 28 pages All Prices Inc VAT at 15% Add 50p Post and Packing. Sae with enquiries. 809. Refundable upon purchase of Antennas.

558 RA DIO CO M MUNICA TION June 1981 D AT O N G' QUALITY PRODUCTS-

A HIGH CLASS GENERALREALISTIC COVERAGE RECEIVER FOR £1 20.753 A OU AR T IN A MKT POTt PRICES!MODEL ASP: THE "INTELLIGENT" RF CLIPPER NO we den I make such a recener bol we re make a convener tor your 2-metre Bigly beautiful sun, up the harliti.al altitude hi antennas and indeed,. Model ASP 'noddies your speech sugnal direCt horn I. rhypCie.Ple and makes all-mode re winch yall turn tt duo gist that 'Model PC I I apples to ransrnatund antennas meo effechve al mOdulating your tranomiller The erred is as it the barerrinter peas You emit then be able lo hear all tho acton on the HF bands plus everythmeelse horn BM lot ruceplen only Me Deane kne ut *Clue Antennas run guinea Mn Prever wend to increase by between two and Imelle lanes 60 Ida/ tO 30 MHz lectrolmg 27 Ml-let tomenllDnal erndom upside dorm Now small n beautiful Unlike Oder speech processors Model ASP a olarrtatiCally si-n'ait y.i vocoal argusbnent of me rout e'en Mel ¡you vall get a you move down to low pree general carom. wavers unterfereme and do not need o armed Mane eve( 10 0001101 the arnbunt Model PCI sounds wee It converts mooning signals in I MN: segments torn 0 Full details are even on our A0270.13370 data of capper). Mil other...se eke One same benefits The led...0 has been provue /036MHz up to the band I 44-145MHz se Devoe. be reconvene. a 2-metre ng tor sheet nut malty these antennas are deat loe by thousands of same'd users crI' Daloog 11w doubt why not apt Dee , even o VHF scannen general coverage DX œrepten holy qiVe For example to moo . ce 6 350 MHz you smpfy sor rne man recover to 144 350 Pospvakint signal toinoise raids tn nuon Weer MODEL 070: THE GO-ANYWHERE MORSE CODE TRAINER. MHz with Modo' PC l sall to ' 06 MHz corm:Mend antennas ow me only 2 metres Seco as PgrOduClein rt 1979 The Mpg is in doing IT. COnverSiOn escena wary TWIN. noise rhreshoict are Model A13370 tong doctor* version e 3 metres overallt overload levels ol the mein recover are not spoilt and so that spuerous responses to They also have a lab response loom 200 kHz to well OVer 30 MHz No eatemat Iras men -us ils aye IsiCCOSO or our Morse Tub> unwonted semis are rruntnused antenna loner iii remand Model A0270 rs for edooa use rm. Model AD370 es offactweress at speeded peoole instead of the CO, dos Sr:hanky umer we use a spomaky developed moo level °weeder. loi .1000e use Trie rattans are denteal through Me Moase .. .atoms peat. .< mixer Tim condones a • 10 aton interceet porn wah extremely tow Remember Ike e me yET mampie above s easy lo make a leery act. legendary and we erect:needy noose plus gain +-Meade/loss Instead el a broadhand wort we use a bank of ea antenna Be a you want ono that deesrne la Me bands will, phantom amnals bead lard success stones by banthaass raters automatcalfy keectea byekode switches *drone at men current A there ts no SUblarlute fOr the careful and thorough design when is Our specially sate-Jed raters I The unContrada frequency synthesiser based on CMOS LS1 generates I they local osollator II you have acres of ground 11,0,, go ahead and erect LIMO Crinventerup record so lar seems to be three freduences me excellent sdeband none levels 'Kenyon antonr.S and tee Wrier unes and atlentlabani Ito Slop sow reneiver weeks to Pan the marn martung Throughout tee cle w we ...red hard to ensure Mai our convener is ahvayS Dere OverIoadeg I on the Menace you want Sondat iesullS unCteulively and Model D70 hom scratch.) Man your 2-metre rog Only Men can you be sure liai you ma eel Me same *retold the. hassle me acorn antennas are unbeatable dillrGenerated 60 hours or random performance nght from 60 kHz to 30 MHz as you got on Me 2-rnetre bard 'noise code tonal. cost 9 volt balfery MOdel 0709w:toy heed°. In WHAT IS AN AUDIO FILTER? It you Already own a 2..metreall-mode transcmver lame( PC I offers. . .wady >act.. anywhere to set your traetable and Mestyle Why buy a Datong auffro Mee peg ierlectryo mute to he ped.rmanoogo maftwegagemcept.on ltwsiainoadiT You loam the code me the Mara. . at normal speed but wer• an antra del-na when yOu can get other mold 60 kHz to 30 MHz coverage to VHF scanned recovers «. eacti hen.] then Ii-00 betwoen each One My*, nspreve yOU reduce the DELAY central untri edit 0 leers al tower prows? To short wave SCanners as well Icily reduced you rind yOU are reading Cede SI Me chosen speed any with answer Ins you test need to THE SAME FOR 2849 MHz RECEIVERS Cdrett spaang You then Co. yam few remember that the tote 'aware BY arldne Our hen performance 2-moire clown-converter. Model OC 144/28 Hier can mean anieung Penmen Model PC1 ard your 26-29 oven down to a cotiple of I yy. VERY LOW FREQUENCY CONVERTER MODEL VU Metz recover you awed as coca, 741's and a handful 01 pans I If yOur co mmunications rot:ewer coverage ri exactly no saine way as Only by COrinparing like with y ewes pod results below 503 deenbed above Sorely tune 28-29 hke can year mate an di/ Model VLF Is the answer MHz on t. Man receive and soleCt informed decisiOn This also adds MW and LW any I Meu bald torn 0 to 30 MHz On rneanS compamg features S. coverage to amateur bands- Model PC% perfoarnance and guably °lile recemes tor news terse Model DC1 e4i28 air.° makes a hoe 2 It you send for our free data sheets and cnoclas Mc n10110 COnverler t leatureS a high compare our products routed ccardethon Connected in sees with the mercept poem Ilmnks to ets balanced M odel FL1 nos wil see that realty there deriver no antenna Model VLF allows you Model DC144/28 Schottky Mode mum Converters mad men at our Chosen Standard of pedm manze to tune Me 010 500 led range ustne dual gate MOSFET S as miner have esultome dynamo range lo match the What Other dude litter can tune ntO heterodyne Medeence lee funeykywhettes land above al reduce0 riupollalmveperlorrmranoeof Model PCl But althOugh we deSigned Model and nolch Morn oul aulconalearly Our medel FLIT Yet MoCel DI t es also sue a sense**, user, me ten mete DCI44 /28 pranardy loe uso velh PCI Ma same noel dynamo range can be per« goort CW fateful:a I aeo Kafir:ISOM Al woe arSthOuSarldS OT baril) 2$-30 MHz) on your Model VLF nee for serious 7 metre 00 work amateurs What other wad lam nas normal rem,. passbano edges shame Man SS8 crystal lams and ern whchtan be tuned al red Products not sho wn in this advertise ment ...on, 200 tb3500 Hi, TOP. or tars Mot our Model FL2 uses no less Man 32 op M odel Datest Transistor Tester amp% plus stale -ol-Ine-ad 1 pulse .7M nvoulaton MORSE KE YB OA R D MODEL MK techndues Two 5-poto M odel Datest 2 Transistor Tester A keyboard Operated morse Sender with a host of features to 0410,1.1 Idlers and a 2-Pole make CW sending a dfeen Model FL2 peat., nOlCh Nee none bos R.F. Speech Processor Model D75 the comPretionSwo character set includes procedure signale and there ate . . .entry tuneable are loor separate 64 character message rherteneS surCh programmed add red M odel RF C/M,R.F. Speech ProcessorPCB Module pirase cababarly Plus a butler thertury for perfect sending respoe Mere filter«) capalploy for SOB FITT, CW than you vell find in any other moo-Met hone Memory centimes are reta nett when s.a.e.:I oft and 'ale lifter - that we know ol answer our queshon then on 'audelaler cony,. alincet anonym On Moocher M odel MPU. Mains Power Unit four eternal pen Cells give an ariiazlbig300rmonrsl,l. Allyou have lode I, plug it info yOur kelnaM' na the phrase "Datong Audio Feet" us a le more precise II stands for stale -on .art ¡Jenne backed by edta capabety meta therouell design ana taiga gamey Accessory Leads • It you need coal melon ask a user.

RE1OLE- 7cillf11 LULLLfIIuI VHF & UHF PREA MPL FIERS: A new range from Ulnch Hansen of West Germany A range of high quality n-line preamplifiers for 2 metres or 70 cms. leatunng ullra-IOW noise ligures and state-of-the-art design The range includes R.F. sw ching capability from 60 watts P.E.P to 500 watts P.E.P and choice of silicon low noise devices or the latest gallium arsenide MESFETs for the best possible noise figure. Indoor or mast mounted options are also included Full details tree on request. These units represent a cost-effective way of improving your OX receiving capability

F il:111 PRICES: All unces include delivery in U I< basic onces are shown with VAT-inclusive prices in brackets. FLI 5800 (6785) 070 4300 (49.45) A0270 + MPU 37 .00 (42.55) FL2 78.00 (89 70) 075 49.00 (56.35) A0370 + MPU 49.00 (56.35) pC1 105.00 (120.75) RFC/M 2300 (26.45) mpu 600 (6 eo) ASP 69.00 (79.35) AD270 33.00 (37.95) DC144/28 31.00 (35.65) Peenaeles.-,„1 0 VLF 2200 (25.30) A0370 45.00 (51 75) )ATO N G ELE CT R O NICS LIMITED IimileiLliàià Spence Mills, Mill Lane, Bramley, Leeds LS13 3HEm England. (012) 552461

RADIO COMMUNICATION June 1981 559 []KDK KYOKUTO MEET THE

SYNTHESIZED = .-

TRANSCEIVER = 144M Hz 25W 12-1/25kHz OMNI-MATCH FOR MORE POWER - BIGGER SIGNALS A recent survey* sho ws how reducing S WR can result in a significant increase in output power, particularly with today's equip ment. To make this reality, we introduce the family of LAR O mni-match's . . . four models cover HF, VHF, Mobile and Linear use, plus an SWL model for receiving.

I • VO-IF KDK 2025 1:11V MA A rr.:J-1 * Custom designed microprocessor control * 25kHz and 12.5kHz synthesizer steps!!

* 'Instant C1SY', 10 times rate button VHF Omni-Match. 144 174MHz. The ATU for the 2-metre man. Enables one * 25 Watts of reliable RF output antenna to cover the whole band. Ends laborious antenna pruning. Tunes out SWR at the operating position. Handles 750W. £3.4.90 * Band scan between any 'easy set' limits * 10 write-in non-volatile memory channels * Memory scanning with hold facility Mobile Omni-match. 1-8 30MHz. 12-ratio impedance transformer matches lower im- * Standard ± 600k Hz or any repeater split pedance of mobile whips. Broadband, no tuning. Reduces SVVR. Increases workable bandwidth. Handles 300W. £9.95 The KDK FM2025E is a 12V de two-metre FM transceiver for mobile or base station use. Although feature packed, operational ease is assured by use of a "custom microprocessor". Digital frequency synthesis provides full band coverage in 12.5kHz or 25kHz steps. "Single krio r frequency selection is by an optically coupled encoder. A Linear Omni-match, 3.5 30MHz. Im- dialling speed switch (increases tuning steps) facilitates rapid OSY's. proves transceiver to linear amplifier mat- A 10 slot memory with Ni -Cad back-up, provides 10 simplex iwith -±600kHz ching. Increases drive for full output, whilst shift) and ior 5 semi-duplex channels, making the 2025 as easy to use mobile as easing load on transceiver. Broadband. crystal controlled transceiver. One memory is semi-dedicated to "priority" and Switched impedances. Handles 300w. programmable when the 2025 is dial controlled. The 2025 embodies the best non-lockout scanner. It scans occupied or empty £9.95 channels and a flick switch enables immediate transmission. The scanner works on the memories and across any selected portion of the band (scan limits are defined by two of the memoriesl. and for good measure Dual gate UHF MOSFETS in the RF and mixer provide superior intermodula- lion performance with high sensitivity maintained over the band by auto-varicap tuning. A monolithic crystal filter in the first IF and a 15 pole ceramic filter in the IkW Feeder Switch. A top quality switch second provides excellent selectivity. with a generous power margin. Up to the The single conversion transmitter uses a balanced mixer and a VCO on the minute styling. £16.95 signal frequency (directly modulated for superb FM) and a hybrid power module for 25W (or 3W) R F. The PA is impervious to breakdowns under infinite VSWR. Necessary control function instructions are programmed into the microprocessor itself. But by re-arranging a diode matrix, the lower frequency HF Omni-match. 1-8 30MHz. Get full band coverage even with high-0 anten- transceive limit, the high frequency receive limit and the high frequency transmit nas, Optimise whole antenna feed system. Avoid power reduction SWR can limit may be altered to allow for changes of band plan or location. bring. Includes new bands. Now scheduled for June/July delivery-- and Switchable auto-tone-burst, RF attenuator, squelch, microphone, it's a winner! microphone clip, power lead, mounting bracket, handbook are, of course, part SWL Omni-match. New design optimised for receiving up to 30MHz. Onus of the package. match ability is now available to the listener. 129.95

O MNI-MATCH TIP NO 3. Match home brew verticals with a Mobile Omn , "What's the catch?" -None(" Compare the specifications, the match. Switch select impedances down to 12ohms. Broad band. 1-8 30MHz features, the construction, the quality and the price. *FREE: 'The Plain Truth about SWR —does it matter?' MORE POWER TO YOU WITH AN OMNI MATCH

INC. VAT AT 15% * Order by post or AND SECURICOR phone your * £199 Access/Barclaycard The 2025 is available fro m the importers or selected dealers number All prices inc. et VAT Add £1.75 for p&p.

SOUTH MIDLANDS COMMUNICATIONS LTD MODULES LIMITED 60 GREEN ROAD TRA DE Telephone OSBORNE ROAD. TOTTON e."9"•- Telex: 477351 SMCO M M G EN QUIRIES SOUTHA MPTON S044DN Tel: Totton 10703) 867333 LEEDS LS6 4JP INVITED 0532 782224

560 RADIO CO M MUNICA TION June 198) AUTHORISED CD) DEALER ...the signof fine com munications Authorised Distributor for TRIO equip ment in Yorkshire and the North East.

THIS MONTH'S LAR SPECIAL- ICOM IC-24G. £169 inc VAT

HS4 Communications headphones, tailored response 10.35 MC50 De luxe desk microphone dual impedance 24.15 MC35S 50K fist microphone (noise cancelling/ 13.80 M C305 500 ohm fist microphone (noise cancelling) 13.80 Price inc. VAT TRIO EQUIPMENT LF30A HF low pass filter I kW 90d13. Stop band rejection 18.40 NEW! Trio KOO multi-mode £345.00 LAR lkW P.E.P. 3-way antenna switch 16.95 R1000 200kHz to 30MHz PLL Receiver with digital readout 285.00 R820 The ultimate matching receiver to the TS820 690.00 VHF AMATEUR RECEIVERS TS830S 160 10M transceiver with the new bands. Successor to the TS820 639.52 sX2CON Programmable Scanner 26-5I4MHz 263.00 VF0230 Digital VFO with memories and digital readout 194.45 SR9 Tuneable/crystal 2m FM receiver 144 146MHz 46.00 AT230 All band ATY and power teeter. Matches TS830S 106.72 AM R2178 Scanner. The best mains/battery operated 120.75 SP230 External speaker unit with switched filters 33.14 DFC230 Digital frequency remote controller. Four memories etc 163.13 HF MOBILE ANTENNAS YK88C 500Hz CW Filter 26.45 YK88CN 270Hz CW Filter 28.75 'G' whip tribander helical 20/ 15/ 10 24.72 'G' whio multimobile 20/15/10 28.75 SM220 Monitor scope 197.80 L.F. coils for the above whips (specify whether tribander or multi- B S8 TS820 scan board for SM220 48.30 mobile) 6.56 TL922 HF linear amplifier 160-10m/2kW P.E.P. 595.70 SP520 Speaker . 17.25 Telescopic whips for the above 3.34 YG3395C CW filter 37.95 Base mounts for all 'G' whips 4.48 TS120V 80 10m mobile transceiver 20 W P. E.P. 347.30 TS130S 8 band 2COW pep mobile transceiver 491.06 VHF/UHF 'J' BEAMS. All 'J' Beam products available TS130V 8 band 20 W pep mobile transceiver 404.34 Famous Ringo Ranger 2m co-linear 27.60 SP40 New mobile speaker unit 26.89 Slim Jim 2m vertical 21.00 TL120 80-10m 200W P.E.P. linear 128.80 GDX2 VHF/UHF Discone Antenna 50-49DMHz 39.50 PS20 AC power supply for TS120V 44.85 MB100 Mobile mourning bracket 17.25 YK88C CW filter 28. 46 ROTATORS SP120 Matching speaker 25.30 Sky King SU4000 86.25 VF0120 Remote VFO 89.70 Sky King SU2000 48.00. PS30 AC PSU for TSI 20S. TA130 Er TS180S 85.10 DR750OR Will take 3 element tribander 107.98 TS770E 2rn 70cm all mode dual bander 730.25 DR76COX Will take a 2 element 40 metre beam 135.00 S P70 Matching speaker 18.40 TR7600 2m synthesised mobile FM 10 Watt 220.00 VHF MOBILE WHIPS A.S.P. (Telecoms Accessories) TA 7930 2m synthesised mobile FM 25 Watt 268.00 T R2300 2m FM portable transceiver 166.75 All ASP mobile antennas and accessories available V B2300 IOW booster 49.45 M B2 Mobile mount 17.25 NEW HF VERTICAL ANTENNA RAI Helical rubber antenna 6.90 HF5 80 10m vertical 48.50 TS180S 160 10m Solid State Transceiver. Digital memory HF5R Operational radial kit for roof mounting 28.00 system. 200W pep 679.65 VF0180 External VFO 96.60 ICOM PRODUCTS SP180 Speaker 36.80 AT180 1.8 30MHz antenna tuner 95.45 C24G FM mobile synthesised transceiver 2m 199.00 P810 Pack of 10 ni-cad batteries 10.36 C.202S SSS portable ILAR PS1200 available!) 2m 169.00 T R2300 Spare power lead 1.30 C211E All mode 2m transceiver 450.00 LAR'PS12C0 Power supply unit and ni-cad charger for TR2200GX/ C255E 25 watt FM 2m mobile with memory and scanner 255.00 TR2300/TR3200 and ICOM portables. You can charge C2E 2m FM hand portable 159.00 and operate at the same time 29.50 C260E 2m all mode mobile 339.00 SRX30 0.5 to 30 MHz SWL Receiver 158.00 C251E All mode transceiver 479.00 HS5 Communications headphones, tailored response 21.85 C720A HF transceiver + Gen coverage receiver 795.00 Securicor delivery arranged if requited

Authorised Distributor for TRIO Et ICOM. C Ty No, HOW TS BUY! a., JAY BEAM, ANTENNA SPECIALISTS, OFF THE PAGE - Simply choose the LIBRARY 27 ›ect HILOMAST and MICRO WAVE product and then complete the 0 MODULES PRODUCTS, PLUS ASCOT coupon and enclose cheque. THE HEADROVV • Open Mon-Fri 9.15-6.00pm Saturday 9.15 5.30pm FROM THE SHOP- We're close to LEEDS AMATEUR RADIO ' H.P. Terms on request the station and car parks. Do call in 27 Cookndge Street, Leeds 2 and see Uncle Tom's cabin! Telephone: Leeds 782224 - Plere tiL + Post to. Leeds Amateur Radio.27 Cookridge Street, Leeds 2. [enclose cheque for Plus 50p for Brochure TO BARCLAYCARD/ACCESS to purchase_ I authorise you to debit my Barclaycard/Access Account Name with the amount of My No. is toseelik Address Pli7-1 RC25 Signature _ RC25

RADIO CO M MUNICA TION June 1981 561 CI) IlL, Tomidal Weston - ANOTHER Western WINNER! TRANSFORMERS IN A RANGE OF The 3eft ULTIMAST 76 TYPES HAVE YOU

We use advanced winding technology to make Our 10rOldal transformers They have only hall the weight and height of their laminated equivalents and are GOT YOURS UP YET? appreciably more effictent Our totoidals cost virtually the sanie as the older types which they are rapidly replacing Induced hum is reduced by a factor of ten Supplied with rigid mounting kit wtrh centre boll, steel and neoprene washers

M mmdra.x3Omm £4.71 30vA Weight 0.45 Kg 160ve mmvlifeZT,, £8.88ic'lsia ge (.11.20 p.p. • 0 89 VAT) ( • r1.80 p.p. • 11.60 VAT) SECONDARY SECONDARY SECONDARY SECONDARY TYPE RMS VOLTS RMS CURRENT TYPE RMS VOLTS RIVES CURRENT IX010 6 1 6 2 SO 5X012 12.12 6.66 IX011 0,9 1 66 5X013 IS. 15 5.33 •••• IX012 12.12 1 25 5%0 14 18 . 18 4.44 ••• IX013 15.15 1 00 5X015 22.22 3.63 1%014 18 • 18 0 83 5X0 16 25 . 25 3.20 IX015 22.22 068 5X017 30 1 30 2.66 1X016 25 25 060 5X018 35 • 35 228 1%017 30 30 0 SO 5X028 110 1.45 5X029 220 0.72 80mm dia. x 3Smm £5.19 5X030 240 0.66 5 0YA Weight 0.9 Kg I+ 51.30 pp. • 0.97 VAT) 2X010 6.6 4.16 225va ZZT,Caux,,45rnm £10.59 2X(111 9 • 9 2.77 ( • E1.90pp. .11.87 VAT) 2X012 12 • 12 208 2X0 13 IS. 15 1 66 6X014 18 e 18 6.25 2X014 18.18 1.38 6X015 22 *22 5 II 2X015 22 • 22 1.13 6X0I6 25 + 2.5 4.50 2X016 25 • 25 I-00 6X017 30+30 3.75 2X017 30. 30 063 6X0I8 35.35 321 2X028 110 0.45 6X026 40 *40 261 2X029 220 0 22 6X028 110 2 04 2X030 240 0 20 6X029 220 1.02 6X030 240 0.93 90mm dia 30mm 80vR Weight 1 Kg £5.76 (ill SO p.p 11 09 VA7) 300 va ee",;Tud211>c`:°mm £12.27 3X010 6.6 6.64 ( 12.00 p.p. • 12.14 VAT) . 3X011 0+9 4.44 3X012 12 * 12 3.33 7X0I6 25.26 6.00 Là 3X013 15+ 15 266 7X0I7 30.30 5.00 3X014 18 + 18 2.22 7X0I8 35.35 4.28 3X015 22 • 22 I 81 7%026 40.40 3.75 The ULTIMAST is a tubular steel two-section mast which is telescopic and tilt-over. 3X016 25.25 1.60 7X025 45.45 3.33 3X017 30. 30 1.33 7X028 110 2.72 Constructed of two steel tubes- the lower square section and the upper round sec 3X028 110 0.72 7X029 220 1.36 tion-- and hot-dip galvanised for corrosion resistance, the ULTIMAST telescopes up 3X029 220 0.36 7X030 240 I.2S 3X030 240 0.33 to 30ft (9m) and down to 15ft (4- 5m). Secured to a square section tubular base post. the mast can be tilted over to only 3ft Il ml above ground for ease of access to anten- 120va ee7iemm £6.72 500,1 =de rm £16.35 nas. Two head units allow clamping of rotor to 2in 150m m) dia, stub, or internal flat f 1.60 pp • 11.25 VAT) (52.1(1 pp. .12.77 VAT) ( • plate mounting. 4X010 6 • 6 10.00 8X017 30.30 8.33 4X011 9.9 6.66 8X0I8 35.35 7.14 4X012 12 • 12 5.00 8X026 40.40 6.25 4X013 15.15 4.00 8X025 45.45 5.55 * Slim and unobtrusive 4%014 18.18 3.33 8X033 50.50 5.00 4X0I 5 22.22 2.72 8X028 110 4.54 * One-winch operation 4X016 25,25 2.40 8X029 220 2.27 * Simple ground fixing 4%017 30 +30 2.00 8X030 240 2.08 4X028 110 1.09 * Self-supporting 4%029 220 0.54 • I.L.P. TOROIDAL TRANSFOR MERS 4%030 240 0.50 ARE GUARANTEED FOR 0 YEARS * For HF and VHF antennas

C H OIC E OF 3 PRI M A R Y INP U TS LP Totaled Transformers are availa ble in choice of 110V 220V 240V coded as COMPLETE TELESCOPIC TILT-OVER £246 .05 follows (Secondaries can be connected in series or parallel) U H D-2 For 110V Primary msert 0 in place of "X . in type number MAST UM-1; for only For 220V Primary (Europe) tnsen 1 in place of "X - in type number For 240V Primary Ili X luriseri 2 in place pl -X" in type number Exampte - 120VA 240V 15.15V. 44 = 42013. FULL PRICE LIST UM-1 Basic mast £15.00 • CUSTO MER DESIGN ENQUIRIES INVITED. QUANTITY PRICE LIST AVAILABLE. U H D-1 Reducing head adaptor £13.25 FREEPOST facitity.(U.K. only). U H D-2 Rotor head unit £31.05 Simply address envelope to FREEPOST to address below NO STAMP REQUIRED All prices include carriage and VA T at 15% TO ORDER Enclose cheque- Postal Order/Money Order payable to! L P LTectronics Ltd or quote your ACCESS or 13ARCLA YCA RD For Scotland-add £10 extra carriage di-count No To pay COI) add it extra to TOTAL value of order C "".. Aloe available horn ELECTROVALUE and MARSHA LLS

MIL W I TRANSFORMERS Western Electronic/ (UK) Ltd A diveacin of I L P ELECTRONICS LTD HEA D OFFICE (All Mail/ Enquiries) FREEP OST T7 GR AH A M BELL HOUSE ROPER CLOSE FAIRFIELD ESTATE, LOUTH, LINOS LN11 OJH CANTERBURY CT2 7EP Tel: Louth (0507) 604955 Telex: 56121 WEST G Phone (02271 54778 Technical (0227) 64723 Telex 965 780

562 R A DIO CO M M U NICA TIO N June 1981 Electionics (UK) WI W estern RIGS for your SUM MER MOTORING —AN UNBEATABLE DUO for HF MOBILE \

YAESU FT-707 TRIO TS-130S

The FT-707 is In the forefront of the new generation of compact HF solid- The TS-130S series is an incredibly compact, full-featured, all solid-state HF state transceivers. Little larger than a book. the FT-707 is a full-feature SSB/CW transceiver for both mobile and fixed operation. It covers 3.5 to transceiver with performance you might expect only in a "top-line" piece of 29.7 MHz (including the three new amateur bands!) and is loaded with equipment. Ideally suited for a home base station or as a mobile travelling optimum operating features such as digital display, IF shift, speech pro- companion. Features digital display. IF width control, LED meter cessor, narrow/wide filter selection (for both SSB and CW modes), and op- system -and of course all new WARC bands! tional (DEC-2301 digital frequency controller. FT-707 £495.00 FP-707 PSU £99.00 TS-130S £479.00 PS-30 PSU £79.00 FC-707 ATU £69.00 YM-36 MIC £10.95 AT-130 ATU £69.00 MC-305 MIC £12.95

...AND A GREAT PAIR OF GENERAL COVERAGE RECEIVERS YAESU FRG-7700 TRIO R-1000 C., E

I . *=---, --;." . — ------..- " le 7 7- 2 4ti ,Ilt. -, • -

i':• i «IMO -i-ei ---,.'" .

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The short-wave listener's dream is now a reality in the One of the best on the general coverage scene. Full coverage 200kHz to FRG-7700- an advanced all-mode com munications 30MHz with digital frequency readout and clock/timer. Switched selectivity receiver featuring significant advances in circuit for optimum performance and other features making it a joy to use and first- design and operating convenience. class value for money.

* VHF UHF SPECIAL OFFER * Only while stocks last . . . YAESU FT-720RV for 2M YAESU FT-720RU for 70cm TR A NS CEIVE R/PS U/E XTE NSIO N CA BLE £295 TR A N S CEIVE R/PS U/E XTE N SIO N CABLE £315

EM OT O ROT ATORS SC AN NIN G RECEIVERS W ESTER N ANTEN N AS ANTEN N A TU NERS VHF M OBILE ANTEN N AS MICR O W AVE M O D ULES DU M MY LOA DS VIBR OPLEX KEYS A NTEN N A S WITCHES STAN D AR D M ORSE KEYS S WR/P O WER METERS HEA DPH O NES CO AX and ROTOR CABLE MICR OPH O NES PLU GS and SOCKETS RIG GIN G ACCESS ORIES

PRICES W E'RE THE KEE NEST IN THE BUSINESS! GIVE US A TRY! . AN D OUR YAESU AN D TRIO HAS A2 YEAR WARR A NTY... ACCESS—VISA CARDS ACCEPTED —HP ARRANGED (WRITTEN QUOTATIONS ON REQUEST) ALL LISTED PRICES INCLUDE VAT AT 15% AND CARRIAGE FAIRFIELD ESTATE, LOUTH, LINCS LN11 OJH UJestern Electronics (UK) ltd Tel: Louth (0507) 604955 Telex: 56121 WEST G OPEN HOURS: 09.00 12.00; 13.00 17.00 Mo m Fri; SATURDAYS 0900 17.00 NORTHERN IRELAND SOUTHA MPTON LEICESTER Mike Matthews, GI8MNO Alan Paxton, G41312 Mays Fi, Churchgate Newtownards (02471 815859 Southampton (0703) 582182 Leicester (0533) 58662

RA DIO CO M MUNICA TION June 1981 563 m eat:rift COR P O R A TI ON

Sole Importers and Distributors

Accessories Ltd. Theme Industrial Estate, Bander Way. Theme, Oxon OX9 3SS. Great 13ritain. Telephone Theme 3621/2,3 Telex 1337206

Available from these dealers:-

Thanet Electronics 143 Reculver Road, Beltinge, Herne Bay, Kent. Tel: 102273) 63859

Leeds Amateur Radio Limited Model No. 32.19 Boomer 27 Cookridge Street, Frequency range IMHz) 144-146 Boomers are your best antenna choice Whatever your choice of 2 metre activity, Leeds. Forward gain dBd 16.2 today. They offer the maximum gain Boomers will fill your needs. For FM at Tel 0532 782224 available for their boom lengths the high end use the 214FB or 228FB. For Front to back ratio dB 24 SWR (typical' 1.2:1 They feature carefully trimmed and cwtssa on the low end use the 32-19 or spaced elements. T•match driven 2148, in EME. DX or regular OSO's Impedance lohm) 50 Amateur elements with 1-1 balun for perfect Boomer will perform for you. Now 220 Weight Ilbl 12 lkgl Electronics UK match. They have Trigon reflectors for MHz has been added to complement the 5.44 Length Iftl 508 514 Alum Road, excellent front to back ratio and cleaner Boomer series. Models are available for 22 Birmingham 8. patterns. Fasteners are all stainless steel the bands from 50 through 229 MHz. Iml 6.71 Turning radius HU Tel: 021-327 1497 ,6313 and heavy gauge heat treated aluminium 11 (mm) tubing rs used for all models. Power dividers are available separately. 3.35 Windload (ft') 3.5 Im'l .33 Amateur Radio Exchange 2 Northfield Road. A3 3 Element 20115/ 10 metres London W13 Make friends of your neighbours with A3 Tel: 01-579 5311 compact dimensions low profile and small turn radius. Satisfy your budget with A3 economy pricing. You will also realise Northern savings by using a lighter weight tower Com munications and rotator. This is one compact beam 303 Claremouni Road. that has the strength and power of most Halifax. larger antennas. Tel: 0422 40792 Forward Gain " 8 tiBd Front to back Ratio (Avg) 25 dBd VSWR 1.2-1 Typical Harvey Lemon Ltd Bandwidth (Avg) 500 KHz 191 Francis Road Power rating 2000 W PEP Leyton, Feed Point impedance 50 ohms London. E10. Boom (ft-in) 14' x 1.63" x 150" tcm) 426.7 x 4.13-3.81 Tel: 01-558 0854 Weight Ilbl 27 (kg) 2.19 Turning Radius If t) 15.50 (m) 4.72

All prices include - - INTERFACE QUARTZ DEVICES LTD VAT and post. G W M RADIO LTD 29 Market Street, Crewkerne, Somerset, TA18 7JU PVE BANTA M LB AM three channel, cloth case and mike, £33. Used batteries AM or FM. Tel: mu 74433 Telex: 46283 inface.g. £6. AC Chargers for three batteries, £15. POCKETFONES PF1 Tx and Fla with circuits etc., E21.25 Re-chargeable batteries. £5.50 pair. AC Chargers for 12 of each battery. £17. ITT FREQUENCY STANDARD. MARKER Er CONVERTER CRYSTALS Sterphones SF1 handhetds UHF with used battery, £36. GEC COURIER AM RC550 HO3C. 5.0, 10.0, 10.7 Er 38.66667MHz 18U £2.70. 1 GMHz SU or 33U f2.95: 100• 0.,Hr 13U or 34U. 79 101MHz with used battery and in original maker's boxes, leather cases and virtually new. 116-0MHt 180 £3.00; 45541kHz 6U £3.50, 200 OkHz GU E3.70: I 0%111z 1, stab SU (4.25 10.131V1Hz hl•stab 360 £8.00 £60. Chargers Sc. £15. CAMBRIDGE L8 Dash with mike or HB boot, no attachments, either CIS. AC Chargers tor Starphone, 14 LMU 8A for 12 batteries, C15. PF5UH with used battery, CRYSTAL FILTERS C25. PF2UB no attachments, with used battery, £35. All used batterie not tested or Super selected 250Mz Etpole CW filters for FT-101, FR-101, FT 301, TS 520, IS 820, FT-901 Et FT •1012 £18.69 each, and 19MHz types with appropriate carrier crystals): guaranteed. except Barmarn and PF1 9MHz SU 6 pole, BW 25kHz at -6dB and 5kHz at -60dB £20.50 RECEIVERS 9MHz SSB 8 pole, BW 2.4kHz at -6dB and 4.3kHz at -60dB £24 00 MARCONI ATALANTA 15kHz ro 29 MHZ. ac supply fitted, £116 4r clean and complete es 9MHz CIN 5 pole. BW 500Hz at -6dB and 2.2kHz at -60dB £2.50 from ship with 115V dc supply. Ob. COLLECTED ONLY. EDDYSTONE 730 480kHz to 9MHz FM 8 pole, BW 12kHz at -6dB and 21.6kHz at -60dB £24.00 10-7MHz FM 8 pole, BW 7.5kHz at - 3dB and 17-5kHz at - 70dB E24.00 30MHz. overhauled and good order. £136 or clean and complete straight from Ministry, £70. 10.7MHz FM Boole, 8W 15kHz at -3dB and 35kHz at -70d0 £24.00 Also 770ft or 7700, £50 either. MARCONI KESTREL 3 Marine 200Ir Hz to 4.5MHz. 12 15V 21-4MHz FM Opole. BW 15kHz at -3dB and 50kHz at -80dB £25.20 dc, solid state, with circuit. £36. All receivers except Atalanta carriage extra at cost 455kHz CFU sedes ceramic filters, various bandwidths in stock £1.50 CB Accessories stocked. TBG-2 crystal tone-burst generator £8.00 40 42 Portland Road. Worthing. BN11 10.N. Tel: 0903-34897 PLEASE ADO 15% VAT POST FREE

564 RADIO COM MUNICATION June 1981 e FM88 2M TRA NSCEIVER Zycom m Z5800 Hand Portable

A no nonsense sythesised rig, free of gimmicks yet offering high power and We are convinced that the FM88 is one of the most reliable 2 good sensitivity. Covers metre rigs being offered today. The construction has to be 144-148 HMz with channels seen to be believed, and all the frills which normally lower in 5 KHz spacing selected reliability have been omitted. by decade switches. Slide switches control simplex or If you are considering buying a new 2 metre transceiver, you repeater and high or low owe it to yourself to consider a unit which has proven itself power operation. Low power level is adjustable by internal with thousands of hours of reliable "on the Air" operation in preset. Maximum power (5 watts nominal) may exceed 7.5 the USA. 25 Watts output. 143-149 mHz in 5KHz steps. watts from internal NiCd battery pack. Antenna has BNC INTRODUCTORY PRICE £178.00 inc VAT connector. PRICES: Z5800 £175.00 inc VAT Desk Charger [19.00 inc VAT 318-F M SCA NNING Remote Mic/Speaker £18.00 inc VAT Full range INCLUSIVE PRICE: £199.00 inc VAT of amateur and M ONITOR commercial antennas end Home Office approved two way Ci-110 Mk2 PO WER AMP radio equipment evadable.

for Pe-

•r, -014 e e z:e e e 001 4 Ak rik Ak 0% 016

A compact unit suitable for fixed or mobile service, giving the option of scanning in user programmed order up to 20 channels in the 430-470 MHz, 140-175 MHz or 68-88 MHz frequency ranges. Manual/automatic and fast/slow scan with channel lockout and delay. Mains or battery operation. Vehicle Mount A Solid State, all modes unit covering 1.7 to 38 MHz. Typical Supplied. power output 130 watts for 215 watts DC input and 4-7 watts PRICE: £95.00 inc VAT drive (15 watts SSB). RF sensing VOX circuit. Switchable STOCK CRYSTALS: S20, 21, 22,23 — RO to 7 — SU 8 and receive pre-amp. Supply requirements: 13.8V at 20A, 20 — RBO, 2, 4, 6, 10, 14 — MO, 6, 10, 16 — 70.26 MHz. Negative Earth. Size: 5" w x 7" I x 3" h. Weight: 2.5 lbs. PRICE: £3.00 each inc VAT. PRICE: £99.00 inc VAT

Agents: Clem Tabor IG3UGR), Banksia, Queen Camel, Yeovil, Somerset 0935-850463 (Evenings Et Weekends only) Alan Kenyon (GW4D00). 24 Connaught Street, Port Talbot, Glamorgan 0639 7963 c o m III Electronics Ltd. Peter Clark (G4IUV), 91 Farmer Road, Leyton, London EIO 5DJ G3ZYC G8CNB G3NJX G3ZYD G8ZYC 01-539 3385 Zy Bob Finch (G4DDM), REF Electronics, Church Road, Pen, 47/51 Pentrich Rd., Ripley, Derby DE5 3DS High Wycombe 049 481.4483 Ted Bowen IG4JKO), Coalville Communications, 6 Ashby Road, Tel Ripley (0773) 44281 Telex 377466 Coalville, Leicestershire 0530-38779 (Day) 0530.60396 (Evenings) 1%. e

RADIO COMMUNICATION June 1981 565 2 ALEXANDER DRIVE, HES WALL ELECTRONIC PRICES SHO WN EXCLUDE VAT WIRRAL, MERSEYSIDE, L61 6XT SERVICES UK CUSTO MERS PLEASE ADD 15% P. M Tel 051-342 4443 Cables CRYSTAL, BIRKENHEAD. CRYSTALS MANUFACTURED T WO METRE CRYSTALS 70cm CRYSTALS TO ORDER Due to the much higher multiplication involved (three times that CRYSTAL .... D on 2m1 all our stock 70cm crystals are to much higher tolerances Prices shown are for one off to our amateur specs: closer FREQUENCY than our standard range. tolerances are available. Please send us details of your re RANGE We are stocking the following channels: RI30 (434 • 60/433. 001. quirements. USE (TX or i = RB2 (434.65/433. M. R84 034-701433.101, RB6 A Low frequency fundamentals in HC13/U or HC6/U and HOLDER! ak (434.75/433.15) SU8 1433.20), RBI° 1434•88/433.25). RB11 Adj. tol. ±50pont. Temp. tot, -1-100ppm O lo .70°C e txX . . 1434.875/433.2751, RB13 1434.925/433.325), RB14 610 19•999kHz £28.12 100 to 159-99kHz £9.25 1434:95/433.35/, SU18 1433.451, SU20 1433.501-TX Et RX for 20to39•999kHz £17.74 160 to 499•99kHz £6 19 i M = OUTPUT 2 use with: RYE UHF Westminster MI5U), UHF Cambridge 40 to 79•999kHz (12.40 500 to 799•99kHz £7.30 3 3

FREQUENCY 18MHz-TX-HC25/U 44MHz•RX-HC6/U 44MHz-RX-HC25/U 44MHz-RX-HC25/U 5.2MHz-RX-HC25/U (wow. PockedonelPF1) AND UHF MO Range, and STORNO 4MHz•TX•HC6/U 4MHz•TX•HC6/U 6MHz•TX•HC26/U 8MHz-TX-FIC6/U 10MHz-RX-HC61U > 80 to 99•999kliz £10.60 - COL /COM 662 all at £2.32. For the U4501. Base Stn we have the B High frequency fundamentals/overtones TX crystals for the above channels. The RX crystals for the Adj. rol 20porn Temp tot. ,3Cippm 10 to .60°C 44•4 1433.21 b b b e U450L Base Stn together with TX and RX crystals for any other 44 •480 e MO e e 70cm channel leg RB/SU12 1434•90/433-30) ATTY. SU16 44•860 s c e (433.401 SU22 1433•551 etc) for most UHF equipments are 900 to 999.9kHz (fund11-1C6/L1 £9.75 44-850 e e e available at £4.48 for crystals up to 63MHz, and £6.16 for 63 to •I .0 to 1.493MHz Ifund) HC6/U £10.36 45•000/ROT a b c 105MHz to amateur spec or £5.26 for up to 63MHz and £8.015 for •1.5 to 2.599MHz IfundlHC6/U £4.93 45•025/R1T a b e 63 to 105MHz to the same closer spec as our stock items. • 2 • 6 to 20• 99MHz 'fund) HC6/U (4.48 45•055/R2T a b e Delivery approx 5/6 weeks. '3-4 to 3.999MHz Ifund)HC18 Et 25/U £6.21 45-975 R3T a b e 4.0 to 5. 999MHz 'fund) HC113 Er 25'U £4.93 45•100/R4T a b e '6-0 to 20•99k4Hz (fund) All holders £4.48 45•125R5T a b e 4m CRYSTALS FOR 70•26MHz- HC6/U as- 150/1161 a b e TX8• 7825MHz and RX6. 7466MHz or 29-7800MHz £2.32 ' 21 to 24•99MHz 'fund) £6.73 45-175/R71 a b e • 25 to 30MHz (fund! £8.28 45•200/R8T a b c 10245MHz "ALTERNATIVE- I.E. CRYSTALS-£2.32 For use 21 to 62•99MHz 13 0, 11 £4.48 45-300/S12 e e O in Pye and other equipment with 10-7MHz and 455kHz I.F.s to • 60to 105MHz (5 0/Ti £5.16 45•350/S14 e a e get rid of the -birdy" just above 145•0MHz. In HC6/U. HC18/U • 105 to 125MHz 15 0111 HC18 & 25/ U (7.76 45-400/SI5 e e e and HC25/U. 125 to 180MHz 10/T1 £7.50 45-425/S17 o e e

£12.49 45•450/S18 a CPW04717CfCtrCren 0 CO b tb 170, e CRYSTAL SOCKETS-HC6/U. HC13/U and HC25/U (Low

180 to 250MHz (0/11 .

45•475/S19 a b 47 e loss) 16p each 10p P. Fi• P. per order IP Er P free If ordered .

45-500/S20 a b 0 c with crystals). •Dellvery Normally 5/8 weeks (express available) - all other Ire. .

45•525/S21 a b 12 c

quencies 7 weeks. . Holders- Low frequencies HC13/U or HC6/U dependent on 45.550/S22 a b c CONVERTER/TRANSVERTER CRYSTALS- HC18/U frequency. 45-575/S23 a b c All at £.00. 38•6666MHz 1144/281, 42MHz (70/281, 58MHz

Mid and High frequencies are available in HC6/U, HC18/U or 45.600/ROR a b CrCr0 c 1144/281, 70MHz 1144/4), 71MHz. (144/21, 96MHz HC25/U unless otherwise shown. 454125/RIR e c 11,296/432/144), 10IMHz (432/281, 101-50MHz 1434/281. FIC17/U 'replacement for FT243) end HC33/U twire end 45•650/R2R e c 105.6666MHz 11,296/28) and 116MHz 1144/281. HC6/U) available as per HC6/U above at 30p extra on HC6/U 45-675/R3R e c price. 45- 700/R4R e c TES tEQUIPMENT FREQUENCY STANDARD CRYSTALS Unless otherwise specified. fundamentals will be supplied 45•725/R5R e c 200kHz, and 455MHz in HC6/U £3.60 to 30pf circuit conditions and overtones to series 45•750/R6R c 100kHz in HC13/U and IMHz in HC6/U £2.96 resonance. 45.775/R7R e c 5MHz in HC6/U and 10MHz and 10.7MHz in FICE/U 45-800/R8R a b c and HC25/U £2.80.

oneogoeutzennnnneemeepennnnneselelnq oneogoeutzennnnneemeepennnnneselelnq e e e CRYSTALS FOR PROFESSIONAL USE 45-950/538 a We can supply crystals to most commercial and MIL specifica- tions, with an express service for that urgent order. Also for corn. PRICES. lal £1.95. lb) £2.32. Cc) £2.50. and (el £4.48. CRYSTALS FOR marcial use, e TV or computer crystals, etc, we can supply at very competitive prices. Please send S.A.E. for details or MICROPROCESSORS telephone between 4.30-7pm and ask for Mr Norcliffe. AVAILABILITY: (al, lb) and stock items normally available by return Iwo have over 5000 items n stock/. 4/6 weeks nor. Please lot us know your requirements e.g. 4MHz HCIBrU EXPRESS SERVICE malty but it is quite possible we could supply from stock. N.B. 1 ell, £2.00; 100 off, £1.10: 1000 off, 99p; 25.000 off. 50p. Many types of made-lo order crystals are evadable on our "EX. Frequencies as listed above but in alternative holders and/or non PRESS SERVICE"- with delivery of three days on our class -A" stock loadings are available as per code tel. service. Telephone for details. ORDERING: When ordering please quote 111 Channel, 121 ANZAC MD-108 TER MS: CASH WITH ORDER - MAIL ORDER Crystal frequency. 131 Holder, 141 Circuit conditions (load in pf). If ONLY-S.A.E. WITH ALL ENQUIRIES-PRICES INCLUDE you cannot give these, please give make and model of equipment DOUBLE BALANCED MIXER P. Et P. (BRITISH ISLES) EXCEPT WHERE STATED- and channel or output frequency required and we will advise if we OVERSEAS CHARGED AT COST have details. 5 500MHz supplred well lull details (or only £6.95.

FREE 15 YEARS P.A. VALVE SUPPLY WITH FT101Z/ZD? RING OR S.A.E. DETAILS. SECURICOR DELIVERY POSSIBLE

UPGRADE YOUR OLD FT101

NEW DOUBLE BALANCED let MIXER. Simple to fit and does improve lire receiver for FT101 MK 11/B E/EE. Not for original F1101 Mk 1. £11.50 inc VAT and post. RF CLIPPER. Models for FT101 Mk Ito FT101E. More receive selectivity and "a better RF O.0.10efl ibeas Se *, Clipper than Yaesu's". That's what we've been told many times. *06.00 inc VAT and post. FM UNIT. For FT101 Mk Ito FT101E. Now only £35.00• inc VAT and post. TX and RX unit ask for copies of reviews of above. Rm. shift £7.00. Tone burst £5.50. 'May be slightly marked br minus engraved (rant panel A 101? SEE THE KNO W YOUR FREQUENCY 101 EXPERTS

10Hz 50MHz 1500MHz") Best DFM we have n. I 1-• tested at anything like price. Sample tested '2,1. Li LI had less drift and greater accuracy than that claimed for professional units at 5 10 times the * SUPER VALUE 13.5V PSU's * “xatris pnce VIA SLO W BOAT FRO M . . . £43.00 inc VAT, post, batteries ARRIVING (WE HOPE) MID-JUNE and input lead. SAE leaflet £23 00 PP1206 6amp DC, Swop surge', £19.90 inc VAT PP138 8amp DC, Ilamp surge', 0.1% regulation', £5.00 inc VAT Typically -.1ppm Guaranteed 0.0002%. Compare!! PP1319 19 amp surge', 12 amp DC', 0.1% regulation', £69.00 Car- riage: Securicor £4 any quantity our risk; £2.50 post at your own risk. BARCLAYCARD OR ACCESS - OR TEMPT US WITH REAL MONEY' , 'Above maker's specification which may be a HOLDINGS PHOTO AUDIO CENTRE, little optimistic. Ask our advice; at this price you can afford to under-run. PSU's are for ham 39/41 Mincing Lane, Blackburn BB2 2AF, radio use only 50/50 duty cycle. Tel: (0254) 59595/6. Closed Thursday

566 RADIO COM MUNICATION June 1981 4 Cross Church Street Huddersfield I Amateur West Yorkshire

Radio NO W IN OUR 21st YEAR -ESTABLISHED 1960

ANNOUNCEMENT Shop NO W AVAILABLE-- THE G4MH MINI-BEA M KIT IL COILS. SPOKES. DO WELS. PLATES. ONLY £55.00 incl VAT P/P C1.50 Tel: 20774 SAE DETAILS

G4MH MINI BEAM

Price: £77.50 + £2.50 p&p in UK PACKAGE: beam, rotator, 15m coax UR43, 15m 5 core-£145.00 Designed and manufactured in the UK SPECIFICATION Element length 11 feet SVVR at resonance 1-5 to 1:00 max Boom length 60 inches Power rating 1400 watts PEP Turning radius 7 feet Input impedance 50 ohms Operating frequencies 10m, 15m, 20m Wind resistance 80 mph Forward gain (ref D pole Weight 14 ibs 1:001 3.6 dB Rotator requirements AR40

SAE for details. Coax UF14.3. UR67 and S core available

IN STOCK - Yaesu Trio - Sommerkamp - Bearcat - S.E.M. J-Beam G-Whips - SN2OON FACILITIES- Instant Hp - Creditcharge - Barclaycard - Access SECONDHAND- Always large stocks, ever-changing - SAE for lists We buy secondhand gear, cash YAESU - FT7B - FT107 - FT901DM FT101Z FT101ZD FT707 FT480 FRG7 - FRG7700 NEW- 2 metre 5/8 wave mobile antenna, 3-5dB with mag mount - only £12 complete OVERSEAS (Whip incl balun, mag mount. PL259 fitted) AGENTS FULL RANGE- SWR inds - coax - keys books - etc REQUIRED FOR ALSO ON DISPLAY- MICROPROCESSORS Apple - Sharp - Video Genie ITT 2020 - Super Board Sorcerer THE MINI BEAM PX WELCOME- We have Hi-Fi - Ham Radio Computers - What have you?

S.E.M PRODUCTS IN STOCK AND ON DISPLAY AT MOBILE RALLIES WE ATTEND Three GREAT G.R.M. FIGHTERS

1. S.E.M. Active C.W. Filter 1. SENTINEL 35 A 150Hz wide needle centred on 750Hz. Not only does the signal stand out but the background 12x Power gain. 3W IN 35W OUT. Max. drive 5W 4 amps. 6" a 21" front panel, 4 deep. (67.50. noise drops 15dB. If you use C.W. you need one. £.26.00. Cit stock. 2. SENTINEL 60 2. S.E.M. Active Notch Filter Five times power gain. IOW IN 50W OUT. Max drive 16W 6 amps. Same size as Sentinel 35. Ex A wide notch for more effect on chirpy C.W. and funny noises. Wide range ICOHz to 10kHz £26.00. stock £69.50. 3. SENTINEL 100 3. S.E.M. MULT1FILTER Ten times power gain. IOW IN 103W OUT. Max. drive 16W. Size Eit"r e front panel. 31.- deep. Adjustable selectivity and frequency. Hi pass. Lo pass. The ultimate "signal sorter- on any modo. 12 amps. Price £126.50. Ex stock. All available less pre-amp for £11.00 less. £67.60. All connect In series with the loudspeaker and require 12V. SENTINEL H.F. WIDEBAND PRE-A MPLIFIERS 2 40MHz 15d8 gain. Ideal for 15 and 10 metres and OSCAR or an ACTIVE AERIAL 9 12V. Sizes: 21" x 11" x r. Two versions. S.E.M. IRAN Z MATCH 1. SENTINEL STANDARD H.F. PRE-A MPLIFIERS The most VERSATILE transmatching system. Wrii match (torn 15 to 5000 Ohms BALANCED or Performance as above C10.00*. Ex stock. UNBALANCED at up to IkW. Link coupled balun means no connection to the equipment which 2. SENTINEL AUTO H.F. PRE-A MPLIFIERS can cure TVI both ways. 160 10M IRAN Z MATCH £67.00. 80 10M £50.013. EZITUNE built in for Same performance as above with a change over relay cl operated by your transceiver for direct £19.50 ewe. S0239 and 4rnrn connections for co ax or Wife feed. connection in your aerial co au. £16.93. Ex stock.

FREQUENCY CONVERTERS S.E.M. EZITUNE SENTINEL DUAL GATE MOSFET 2 metre or 4 metre CONVERTERS. N.F. 2cIB. Gain 30dB. I.F.s A new concept in -tuning up-. 50 Ohm bridge, noise generator and r.f switch allows you to 2 metres: 2 4MHz, 4 6fv1Hz. Of 28 30MHz 4 metre 28 28• 7MHz. 9 12V 15mA. £24.73. Ex stock. match your aerial without transmitting. Save P.A.s. Stop O.R.M. for EZ8.75*. SENTINEL X 2-METRE CONVERTER THE SENTINEL AUTO 2 METRE PRE-AMPLIFIER Same as above plus mains power supply M K Ex stock These include NEW PROTECTION circuit to give MAXIMUM LEGAL through power rating. Corn- pletek/ new third generation DUAL GATE MOSFET pre-amp giving ldB N.F. and 20dB gain with SENTINEL L.F. CONVERTER GAIN CONTROL and OFF switch (straight through when OFF). The High 0 tuned circuits for high 10kHz-2MHE IN. 28 30MHz OUT. 9 12V 5mA. (20.130. Ex stock. selectivity. I2V 25mA. Sizes 11" x 21 £26.001, 70cm version E28.00'. All ex stock. SENTINEL TOP BAND CONVERTER 1.8 2.3MHz IN 14 14 SMHz OUT 9 12V 5rnA £20.80. Ex stock. SENTINEL 2 METRE LINEAR POWER AMPLIFIER/PRE-A MPLIFIERS The units use the latest techniques and transistors for highest reliability and performance. Infinite 12 MONTHS' COMPLETE GUARANTEE swil PROTECTED devices. ULTRA LINEAR, all modes R F. switched. Same POWER GAIN at Prices include VAT and delivery. C.W.0 or phone credit card number for same day service lower drive powers. Supply 13.8V nominal. Three models. 'Means Belling Lee sockets. add 11.90 for S0239s or BNC. Ring or write for more information

OVER 2000 sq.ft SHOWROOM AREA Our Staff: Jim G4MH, Ray G810F, Chris G8PUT, Ted G3UUA, Norman G3WAH Open Mon Sat 9.00am to 5.30pm, late night Thursday till 8.00pin. Send 50p for our comprehensive catalogue. Trade enquiries welcome.

RADIO COMMUNICATION June 1981 567 SOUND ADVICE SOUND VALUE

A GOOD START is essential to short wave listening and expert advice is important in achieving this- So here's some-If you've made up your mind to buy a receiver you should be aware it will perform only as well as the antenna it sees. The old adage regarding wire antennas "As long and as high as you can" is still good, but at best is only good for PEAK PERFORMANCE on one or two frequencies, at worst none. Whichever frequency you tune your receiver to, for PEAK PERFORMANCE on all frequencies you need good matching between your Receiver and Antenna to hear the best from it. If you plan to listen on the high frequency bands up to 30MHz then you know you can't have an antenna for every frequency! Or can you?- Well not quite! BUT we can offer you MUCH IMPROVED PERFORMANCE from your receiver by using an antenna tuning unit, that will electrically change the length of your antenna to match the frequency you select- in other words-A MATCH AT ALL FREQUENCIES. You'll see many antennas being advertised under gimmicky names, but when it comes down to it they're only random wires or odd configura- tions. At the end of the day, if you're expecting the performance the manufacturers specified, then you'll have to buy an antenna tuning unit. Tell you what we'll do- we'll prove to you -we'll give you one ABSOLUTELY FREE when you buy your FRG 7700 or FRG 7700M and we'll give you complete advice on an antenna to suit your available space, which should only cost you a couple of pounds! So let's put the offer in big print for you!

1 YAESU FRG 7700 + AMTECH 200 ATU £309.00 1 YAESU FRG 7700M + AMTECH 300 ATU £389.00 VAT included

What's the difference between the Amtech 200 and Amtech 300? Well both will tune any random length of wire but the Amtech 300 will do a little extra-it will also tune co-axial fed antennas- Their normal selling price? The Amtech 300 f43.95- The Amtech 200 £.95- What can you lose? So get cracking MAKE A GOOD START! HAVE PEAK PERFORMANCE FROM THE OFF.

JAYBEAM - HYGAIN - BANTEX- AMTECH - CUSHCRAFT- SWAN - ATLAS and 50 other major lines- all ex stock AMCO M M SERVICES AMCO M M 194A NORTHOLT ROAD, SOUTH HARRO W, MIDDX. LONDON. Tels: 01-864 1166 M M../ \e/ vats') Et 01-422 9585 Opening hours: Tues Sat 9.00 5.30, Sundays by appointment. Closed Monday..

Prrtic, W ARD ELECTRONICS -rizezo G3X WX G4CLX

TR-9000 £345.00 TS-830S £639.52 TS-130S £491.05

9 Band 1160 10m1 coverage. Flexible 2m multimode -all the facilities 8 Band (80 10m) 200W PEP input IF tuning and RF speech processor for you want at a price you can afford Solid State Transceiver optimum receive and transmit capability

TS -180S 160 10m deluxe solid state KX-2 SWL AT') £29.90 HFDX Predictor transceiver E679.65 Cross pointers power meteril All programs on tape at £5 each PS.30 PSU for 180S or 130S f85.10 CN-520A 1.8 150MHz £52.81 R•1000 general coverage receiver. High sensitivity CN 630 140 450MHz £71.00 tuning accuracy and stability tzes.00 * * * A snip for April WIRECUTTERS £1.00 per pair TS-120v 10W 80 10m. E347.30 excellent quality. * NEW *TR ,840070cm synthesized FM £279.00 APPLE ll Microcomputer £799.00 DM81 GDO 700kHz 250MHz £51 75 TR ,78002m deluxe FM f268.00 EG303 Microcomputer £365.00 FXI Wavemeter 700kHz 250MHz E28.00 TR-2300 The popular do.anything. go-anywhere Computer books and storage media for callers DR750OR Rotator E106.00 FM rig £16675 Cassette discs. Printed paper. RM940 Mobile mie £45.00 VEI-2300 FM 10W amplifier tor TR2300 £49.45 Amateur radio software from PLASMA SR9 VFOr Crystal FM RX [46.00 HS.5 Trio deluxe communications headphones... f21.85 Morse trainer. Avey line DX paths St.1600 Scanner E39.50 HC.1400 Synthesized FM. E189.00 ORA Locator/distances. Hi/Lo pass filters Lowe SRX3OD 203kHz 30MHz, 1195.00

A4040 RING ROAD ALL BOULTON FROM WARD ELECTRONICS PRICES TO CITY ROAD Adl M5 SOHO HOUSE (First floor) 1 SHO WN 362 4 SOHO ROAD, HANDS WORTH SOHO ROAD * EXIT 1 INCLUDE BIRMINGHAM B21 9QL. Tel: 021-554 0708 VAT AT OPEN TUES SAT A4040 ROOKERY CAR 15% Also evenings and weekends ROAD PARK Ring Tony, G4CLX, on Kidderminster 851255

568 RADIO COM MUNICATION June 1981 ANOTHER FIRST FRO M STANDARD-THE NEW C58 FM / SSB/ CW TRANSPORTABLE

The C58 is the ultimate 2 metre transportable offering a superb performance on FM /USB/LSB ts CW unequalled in any transceiver to date. The C58's small size makes it truly a portable and when used with the CM8 mounting cradle it has all the features, and more, of a mobile multi-mode transceiver.

UNIQUE L.C.O. The lcd display has been purpose-made for Standard and it not only displays the frequency down to 100Hz but also supplies scanning and memory details. The main advantage with the lcd display is the low power consumption which is a must for portable equipment. For night use the display can be illuminated.

ME MORY/SCANNER The C58 has five memories that can be user-programmed from the front panel controls; these memories not only retain the frequency but also the mode at the time of programming. When the memories are scanned the scanner will look only at those channels that have been entered in the correct mode; ie: if out of five channels three have been entered in the FM mode and two in the SSB mode, then on scan with the mode switch in the FM position Me three FM channels will be scanned this is displayed on the lcd). When the mode switch is in the SSB position only the two SSB channels will be scanned. This type of intelligent scanning can be found only in the Standard range at the present time.

RELIABILITY As with all Standard equipment the reliability is assured by their excellent quality control and years of experience in the professional communications market We can endorse this by the lack of Standard equipment we find in our service laboratory,

ACCESSORIES The accessories for the C58 are the same as those for the C78 (with the exception of the power booster/. which allows interchangeability between the units.

FEATURES * Liquid Crystal Display * Full scanning facilities * 100Hz/lkHz/5kHz Et * Automatic/manual 25/12.5kHz tone-burst * Five programmable memories * One Watt RF power * Rit Control * Up/down scan on * Repeater Et rev, repeater microphone off set * Battery saver * Effective noise blanker

THE DYNA MIC DUO

ACCESSORIES FOR BOTH

CL8 carry case with straps £6.95 inc VAT C M8 mobile mounting cradle £17.95 inc VAT C230 12 240v charger £7.95 inc VAT

NCO set of re-chargable Ni -Cads £11.00 inc VA I- CPB78 10 Watt amplifier for C78 £65.00 inc VAT CPB78 10/25 Watt amplifier for C58 TBA

LEE ELECTRONICS LTD HF Et PART EXCHANGES 400 EDG WARE ROAD, LONDON W2 WELCO ME Tel: 01-723 5521. Telex: 298765 SAE FOR FULL DETAILS

RADIO COMMUNICATION June 1981 569 FOR QUALITY CRYSTALS-AT COMPETITIVE PRICES. POPULAR FREQUENCIES IN STOCK - MADE TO ORDER 10kHz to 225MHz RB15 Pocketfone crystals now in stock 2 METRE STOCK CRYSTALS. Pr,CC £1.83 for one crystal. £1.74'CryStal M ee Iwo or purchased HC8/U HC6/U HC25/U HC2511.1 HC25/U HC6 Ft SU M MER HOLID AYS 30pF and 20pF and 25pF and 25/U 30pF TX 30pF TX 40pF TX 30pF RX 20pF TX SR RX Please note we shall be closed for annual holidays fro m 8 August to RO 4-0277 8-0555 12-0833 14-9888 18.1250 44•9666 29 August. Any inconvenience to our custo mers is regretted R1 4-0284 8-0569 12-0854 14-9916 18.1781 44-9750 M ADE TO ORDER CRYSTALS SINGLE UNIT PRICING R2 4.0291 8.0583 12-0875 14-9944 18-1312 44-9833 Adjustment Price and R3 4.0298 8-0597 12-Q895 14-9972 18.1343 m 44•9916 Price Tolerance Frequency Delivery R4 4-0305 8-0611 12.0916 15 - C000 18.1375 45-0000 Group PPm Ranges A R5 4.0312 8.0625 12-0937 15-0027 18.1406 45-0383 Fundamentals 1 200 (total) 10 to 19-999kHz £23.03 R6 4-0319 8-0638 12-0958 15-0055 18.1437 45-0166 2 200 (total) 20 to 29-999kHz £16.50 R7 4.0326 8-0652 12-0979 15-0083 18-1468 45 -0250 3 200 1101011 3010 99•999kHz £0.50 58 12-1000 14-9444 18-1500 )8 44-833.3" 4 200 Itotall 100 to 999-999kHz £6.00 59 12-1020 14-9472 44-8416" 18-1562 44-850018. la31 s 50 1•00 to 1-499MHz £9 00 £6.00 SIO 12-1041 14.9500 - 6 10 1.50 to 1•999MHz £4.75 £4.20 18-1593 44-8583" 511 12-1062 14-9572 7 10 2.00 to 2•599MHz £4.75 £4.00 S12 12-1083 14.9555 18-1625 44• 8666" 8 10 M O to 3•99'3MHz £4.55 £3.70 513 '12-1104 14-9583 18-1656 44•8750 9 10 4-03 to 20• 999MHz £4.56 £3.60 S14 12-1125 14-9611 18-1687 44-8833 10 10 21-03 to 24- MHz £6.00 £5.40 S15 12-1145 14-9638 18-1718 44•8916* 3rd OVT It 10 21.03 io 59•399MHz £4.55 £3.60 516 12-1167 14-9667 18-1750 I 44:9 L0•. 5th OVT 12 10 60.00 to 99•999MHz £5.00 f4.00 S17 12-1187 14-9694 18-1781 r) 449 ..., 13 10 100•03 to 124.9 %MHz £6.15 f5.20 S18 12-1208 14.9722 S19 12-1229 14-9750 18-1812 a' 44• 9166' 5th. 71h ft 14 29 125.00 to 149.999MHz £6.00 18-1843 g 44-9250' 91r, OVT 15 20 150•00 to 225. OIX1MHz ri.$) S20 4-0416 8-0833 12-1250 14-9777 18-1875 '.- 44 -9333 18-1906S21 4.0423 8-0847 12-1270 9805 522 4.0430 8.0861 18-1937 1414 -.9833 44-9512-1291 44.9416 Unless otherwise requested fundamentals wal be suppled with 30pF load capacity and over- 00 tones for series resonance operation. S23 4-0437 8-0875 12-1312 14-9861 18-1968 44-9583 HOLDERS -Please specify when ordering 10 to 200kHz HC13,1.1,170kHz to 170MHz HC6 or Also In stock: RO to R7 and S8 to S23 for following: Belcom FS1007. FDK 7M56. Multi 11 HC3.3.U. 4 to 225MHz. HC18 and HC25. Quartz 16 and Multi 7, lcom IC2F. 21.22A and 215, Trio Kenwood 2200, 7200, Uniden 2030 and Yaesu FT2FB, FT2 Auto, F7224. FT223 and FT202. DELIVERY Column A 3 to 4 weeks. Column 6 6 to 8 weeks. Also In stock: 4 and 8MHz TX in HC6cU for 145.8MHz. corn crystals TX for 145-6MHz DISCOUNTS. 5% mixed frequency discount for 5 or more crystals at B delivery. Price on ap- IRROI 44MHz RX crystals in HC6 for 145.8 and 145 IFIROI. All at above price plication for 10 or more crystals to same frequency specification Special rates for bulk purchase. 4 METRE CRYSTALS for 70-26MHz in 1-1C6ill at '£2.25. TX 8•78250MHz. RX 6-7466 or schemes including FREE supply of crystals used in UK repeaters. 29 • 78MHz in stock. EMERGENCY SERVICE SURCHARGES (to be added to A delivery pricesl. 4 working days £12. 70cm CRYSTALS in stock 8-0222 and 12-0333 in HC6 £1.85. Pye Pockedone PF I, PF2. PF70 6ezoorkinry ig days f7. 8 working clays C5. 13 working days f 3 (maximum of 5 crystals on 4 day and Wood and Douglas £4.50 a pair or TX £2.25. RX £2.50, SU8(433-21RBO. RE12, R84. R136, d R810. RB11. RE113, RB14 and R815. CONVERTER CRYSTALS in HC18.1.1 at £2.85. In stock 38• 666. 42-000, 70.000. 96-000. CRYSTAL SOCKETS HC6'U and HC25fU 16p. MINIMUM ORDER CHARGE £1.50. 101-000, 101-500. 105-666 and 116.000MHz TER MS. Cash with order. cheques and postal orders payable to QSL Ltd. All prices include TONE BURST AND I.F. CRYSTALS in HC18'll at £2.25 in stock. 7•168MHz for 1750Hz and postage to UK and Irish addresses. Please note Southern Irish cheques and postal orders are no 10-245MHz for 10-7MHz 1.F 's longer acceptable Please send hank draft in pounds Sterling. FREQUENCY STANDARDS in stock £2.75, HC6 200kHz, 455kHz. ICOOkHz, 5•000MHz and 10.000MHz HC13 100kHz. HC18 1COOkHz. 7-0 03M1-Ia. 10•700MHz. 48-(XX/MHz and PRICES ARE EX VAT. PLEASE ADD 15% 100• 000M H7 MARKETING LTD. P.O. BOX 73 SUM MIT HOUSE, LONDON SE18 3LR lpuartSLab Telephone: 01-690 4889 24hr Ansafone: Erith (03224) 30830 Telex: 912881 CWUKTX-G (Attention QUARTSLAB). Cables: QUARTSLAB LONDON SE18

.....,,,.,_-_„.,..___.,..„..... S C (Leeds) South Midlands Com munications Limited

Cr co m modore

‘.0.4rnie irn`id,..W. L'Ott 'el« , ickr,t4o,f•Cf Atk a.) The ONE STOP SHOP IT'S THE WINNER! ....« ..--- for the latest o- . :=-, in amateur com munications technology The Sussex Mobile Ral ly 11 .1111 00k M UP D ATE YOU R STATION Send N O W for new price list (THE ONLY RALLY WHICH CATERS FOR THE WH OLE FA MILY). AUTHORISED DEALERS FOR CO M M ODORE PET b KIM MICROC O MPUTERS AND ASSOCIATED PERIPHERALS.

SUNDAY 19th JULY Easily accessible by road, we are located on the A660

r\' ei four miles north of Leeds city centre and 400 yards 10.30 AM-6.00 PM from the A6120 ring road. Bus services 1, 4, 96 and 755 amongst others stop outside the door, and car C e ' C O W parking presents no problems. Apart from the SMC

BRIGHTON RACEGROUND 3"1 , lines advertised elsewhere, we consider we stock the RACEHILL, BRIGHTON, E. SUSSEX largest selectio of Jaybeani and Micro wave Modules ..I» n inthe North ofEngland.

ENTRANCE 50p (UNDER 14 et DISABLED FREE) G3PS M G8S MC

FREE PARKIN G FOR OVER 4.000 CARS BARCLA YCARD HIRE PURC HASE PART OVER 20.000 SO FT. EXHIBITIO N ARE A UN DER COVER EXCHA NGE- A CCESS A PLEAS URE

ALL THE DET AILS IN NEXT M ONTH'S RADC O M. 257 OTLEY ROA D, LEE DS, YORKSHIRE LS16 5LQ OR FRO M J. TRIM MER G4JD M 102731 693695 Telephone: Leeds 105321 782326 (OFFICE HOURS) EXTN. 2266 Monday to Saturday open 9 5.30prn

570 RADIO COM MUNICATION June 1981 BUY ONE "'TAKE ONE A YAESU SPECTACULAR FROM THEIR NUMBER ONE UK RETAIL OUTLET WITH FULL FACTORY BACKED SERVICE.

AND TAKE

1 Skymaster 4000 Rotor Worth £85.00 or Free 1 Astatic Silver Eagle Mic Worth £50.00

AND TAKE 1 Shure 526T Mic • e .11Ë. Worth £40.00 ▪ e Buy this FT101ZD at £569.00 or 1 Oskerbloc or Free gm till% 200B SWR/PVVR • Meter Worth £40.00 g AND TAKE 1 Shure 526T Mic Worth £40.00 or Buy this FT707 at £529.00 1 Killowatt Dummy Load Free Worth £35.00

AND TAKE

1 AR40 Rotor Worth 59.00 or Buy this FT225 RD at £565.00 1 Shure 526T Free Worth £40

AND TAKE

1 Jaybearn 4 Element Quad Worth £23.69 or 1 Jaybeam Buy this FT480 at £359.00. 8 x y/2m Free Antenna Worth £28.40

Amcomm Services 194 Northolt Road, AMCO M M SERVICES Please send in. South Harrow, 194 NORTHOLT ROAD, SOUTH HARRO W, MIDDX. Middx HA2 ORN. .enclose0 cheque ,P 0 for Telephone: 01-864 1166, 01-422 9585 Opposite South Harrow Tube Station on Piccadilly Line or charge rhy V ISAiACCESS ALL ITEMS INCLUDE VAT+ CARRIAGE Name

Showroom Opening Hours: A OcneSS

Tuesday to Saturday 9.00 - 5.30 Sunday by Appointment P., Code

RADIO COM MUNICATION June 1981 571 Bedford 0234 854133 fiJUIOEDiiiiti

76 BEDFORD ROAD, KEMPSTON, BEDS AUTHORISED DEALERS FOR: YAESU • FDK • JAYBEA M MICRO WAVE MODULES • BANTEX RSGB PUBLICATIONS, ETC

PLUGS, CONNECTORS, CABLES, ROTATORS, KEYERS, MOBILE Er BASE MICROPHONES, PSU's, ETC, ETC (SEND FOR LIST)

VF 7401-2 2 Metre Digital Scanning CREDIT SALE, ACCESS, BARCLAYCARD Transceiver. AND OUR OWN CREDIT CHARGE CARD Fullysynthesized. 15 watt solid • state rig. Scanning Capability. Mobile or fixed station use. OPEN TUES-SAT COME AND VISIT OUR 'SHACK' SOON G8XIE

THE ROBOT "400" SSTV SCAN CONVERTOR revives the parts the other gear can't reach and restores the thrill of your first (ISO. Still only £666 inc VAT HW-8 QRP CW Transceiver. 80m through 15m. 3.5W DC Please send 14p stamp for full details power input. Operates from car battery or mains pack. AERO Et GENERAL SUPPLIES Biàig 33, art Pfeclands Airpxt, Castle Donington, Derby. Tel: D332 812446 IM-2400 Hand•held Frequency Counter. Measures 50Hz to 512A1Hz in two ranges. 7 digit LED Display. Crystal•controlled 10MHZ time base. Operates on nickel•cadmium batteries or linecurrent withoptional TELECO M ICO M eliminator charger. Swivelling Telescopic Antenna optional. RECEIVERS VHF TRANSCEIVERS FRG7 £169.00 IC2E £159.00 IC260E £399.00 Make Heathkit your first choice for building Amateur FRG7D 165.00 IC202S 169.00 IC251E 479.00 IC255E 255.00 IC24G 199.00 Radio Kits of Quality. Easy to build. And superb value for FR G7000 259.00 SANYO 204.00 IC280E 250.00 IC720A 796.00 money. RIM/ 285.00 CLEGG 2M. 199.00 Full details are available in the Heathkit catalogue. Send P.S.U.s 13-8V 3A 15.00 for your copy and see the Quality choice now. 13.8V 6A 16.50 ACCESS/BARCLAYCARD/HP IC3PE 59.00 Callers welcome Mon/Sat To: Heath Electronics (UK) Limited. Dept. (R(.76). Bristol ICBC30 34.00 6 NEW STREET, BARNSLEY. YORKS. Road. Gloucester, GL2 6EE. PLUS ALL ACCESSORIES TEL: 0226 6031 (DAY) 0226 382320 Plea'se send me a copy of the Heathkit catalogue. I enclose 28p in stamps. Name Address HIGH QUALITY CABLES FRO M G8M W W IM M MEein UR43. 50 ohm, 20p per metre IPott 21p per in) UR78, 50 ohm, wended conductor. 22p per m IP/P 2*p/ NB: If you are already on the Heathkit mailing list you will rep U M, 50 ohm, thick low loss. 8_01* per m (P/P 41p1 Soldering automatically receive a copy of the latest UFI96, 50 ohm, miniature nylon. 26p perm (Pis 1p) All prices UR7O, 75 ohm. 5rnm dia, 29p per mIP/P2}ro include VAT Iron offer Heathkit catalogue without having to use this coupon. LOW LOSS UHF TV FEEDER, 75, ohm, 18p perm (P/P 21p) FREE When you receive yourcatalogueyou will get details of this 300 ohm TWIN RIBBON, 11p perm IP/P 190 free offer. 76 ohm TWIN FEEDER, 18p perm (P/P 2p1 14 SWG hard drawn copper aerial Wire, 111p perm (P/P 21p) HEAVY equipment wire, PVC covered, OK for Ae wire, 6p per m (P/P 2pl PTFE Silver plated and screened wire, 20p per m (P/P 1p) MULTICORE SCREENED. 8 core, 15p/m 20 core. 26p/m (P/P 4p) (in up to 27 feet cods) SAE for full lists . . or ll you need er sample of any of above. HEATH WT W. H. Westlake, G8MVVVV, Clawton, Holsworthy, Devon 572 RADIO COM MUNICATION June 1981 I T' S ALL AT ARRO W

"Didn't kno w you stocked those", they said. "Oh, yes!" we said, "plus Yaesu Musen, Standard, Shure, Micro wave M odules, Hi•Mound, CDE, Stolle, Vibroplex, Teleco m m, Cushcraft, Swan ...". "OK, that's enough", they said. "I'll send for your list-ho w much?" "FREE, of course", we said. "But a sta mped addressed envelope would be nice."

- -.-. --ii .. " 7.1 K .-- e •'. .- - - .. , .a. ' • e e- .... CI. 1 • • ...Ur — - ARRO W now stock hei. , T S280F M _ ___.. , .. * 4 versions of ._ £199.00 - - . . . • — this excellent - • -- _ . . transceiver: =L -- .7. • ,-- , .i. a ms.ribm-- - - ' C i_fp -• Al ; ____ _ •• • •

World's most compact 80 channel 50W 2 metre mobile rig. With auto select of repeater/simplex. Digital readout of channel. AND NOW WITH VOLUME CONTROL ON MIC AND AUTOMATIC FT101 Z with Analogue dial £445.00 TONEBURST RO R7 PLUS INPUT MONITOR CAPABILITY. FT101ZD Digital - WARC version £569.00 (Optional extra). FT2T7ZD Sommerkamp Digital -- WARC and all options £649.00 TS280LP NEW LOW PRICE £159.00 FT101ZD Mark 3, WARC Et FMI' £599.00 16VVatt version 80Ch NO W WITH AUTO TONEBURST RO-R7 Et INPUT LISTEN. (Optional extra). --- • --- - 'I' Two versions of the _:. -..".-11- - -. -- '''''3' 1 II IM ' -Wayfarer" from stock. 91114 .1 4.414 '- ) - . - ,

N O W ST O C KIN G: i — - o ...- c, FT707 Yaesu £529.00 ' _ - C -- FT767DX Sommerkamp with CW Filter Ft Mic £579.00 ..... rm. -

... . ---, FREE THIS FT107 Yaesu Basic set £890.00 -. - - .a. - - e :,...7.7 . M ONTH WITH FT307D MS Sommerkamp with Int. PSU Et OMS unit. Mic. POA , 7 -iirii e- em e r.7.):à ' RECEIVERS

•:_;;;7:- N, 41) -1 '-' ' F j M OT FRG7700) A N D S O M E O F T H E R E S T: -4,--- .,.._- - HEA DP H O NES -. I 0. e _) .....ii e ^ 0 by YAESU FT7B - Still one of the best HF Mobiles- with mike and mobile mount £399.00 - - R1000 Kenwood £2i39.00 C8800- Standard 2m FM mobile with digital display, scan with Microphone FRG-7 Yaesu £189.00 control: come and see it f252.00 FRGT700 Yaesu £309.00 FRGT700 - Mem. £389.00 C7800- Standard's beautiful 70cm FM Box. Really nice unit. scans. mie FRG7000 (259.00 control etc. £275.00 I-1 7R 12-5kHz model with leather case, nicad, and Helical £195.00 NC3A Slot in charger n e w SX200- Revco's super scanner with 26-514MHz (less a couple of gap e) YM24 Speaker Mic. £16.85 Clock, Digital display. 16-channel memory and much more ... £239.00 M ASPRO 7/8 wavelength 2m antennas now in £17.85

VHFL- Newdisconeantenna for theSX203 or sim £17 .95 NE W: 2 metre ground planes beautifully made 6dB gain £34.95 70cm version 6dB gain £34.95

IC2E ICO M's famous "pocket - portable supplied with free leather case £159.00 PLEASE SEND FOR OUR 1981 LIST, MAYBE THERE WILL BE SOMETHING YOU CAN'T GET ELSE WHERE-REMEMBER ALSO OUR LARGE COMPONENT STOCK IS STILL AVAILABLE MAIL ORDER-PLEASE ASK IF DP1 - Trap Dipoles for 80/40/20/ 10 or 8W40 / 15 10 from stock £25.30 YOU'D LIKE A COPY OF OUR COMPONENTS LIST. - REMEMBER ARRO W ONLY STOCK FOR THE AMATEUR Er ELECTRONIC G4MH - "Jim's" famous beam from ARRO W. a two Element for 20 '15' 10 for ENTHUSIAST WE DON'T OFFER YOU A SHO WROOM OF DOMESTIC HI-Fl Er £79.95 cant be bad" ONE EYED MONSTERS"

A LL-IN P OLIC Y: ALL A D VE R TIS E D P RI C E S IN C L U D E T A X A N D FR E E D E LIV E R Y (SE C U RIC O R F O R RI G S)

. ARROW ELECTRONICS LTD Access :Seeusat 7 Coptfold Road, Brentwood, Essex CM14 4BN Tel: 0277 226470 or 219435 Ansafone on 219435 Telex: 995801 1 1 Open 5 days a week. Closed Thurs. BARCLAYCARD

JUNE 14th J.' A C CE S S • VIS A • INS T A N T H P • T W O YE A R S' W A R R A N T Y VISA , • B E S T TR A D E-I N P RIC E S NEW 1981 CATALOGUE FREE ON REQUEST (SAE PLEASE)

73's FR O M G 3L S T - PE TE R : G 6 A K L - B O B : K E N - F A Y - B R E N D A - O LIVE

RADIO COMMUNICATION June 1981 573 uNEARics THE LOWEST PRICES FOR PRIME CMOS/TTL/74C IN THE UK .1000 sm.., 060 0.95 7448 0.56 74125 040 74190 0.55 7405 3.14 7496 1.20 74190 0.60 74C CMOS 8E194 18p 713.11200 1 09 St 1610P 1 iA) 16111773 215 4566 1.59 01.1611P 160 1.45 4000 0.13 4063 1.15 7450 0.14 74126 0.40 74191 0.55 7408 0.14 74107 0.25 74191 0.60 0E195 18p 1200 1 95 HAl 1 225 45138 2.18 02378 ; .28 5L1612P 1.60 HA 12002 1.45 4001 0.13 4066 0.38 7451 0.14 74128 0.65 74192 0.55 7409 0.14 74109 0.25 74192 0.68 7400 0.20 06224 22p 4002 0.14 4067 4.30 4569 1.95 7453 0.14 74132 0,50 74193 0.55 7410 0.13 74112 0.25 74193 0.68 7402 0.20 8E241 18p 117.111.1 I 28 011613P 1.89 HA12017 0.80 4572 0.30 02571.1 1 28 51.162OP 2.17 HA12402 1.95 4007 0.19 4068 0 8 7454 0.14 74136 0.65 74194 0.55 7411 0.14 74113 0.25 74194 042 7404 020 11E274 18p 4582 0.99 13E440 210 026714 I 28 01.1621P 2 17 itA124 II 1.20 4008 0.70 4069 0.18 74613 0.14 74141 0.45 74195 0.55 7412 0.15 74114 0.25 74195 0.42 7408 0.20 4009 0.30 4070 0.26 4584 0.49 7470 0.28 74142 1.85 74196 0.55 7413 0.28 74122 0.40 74196 0.65 7410 0.20 66441 21p LI1130111 0.67 SL 1623P 2.44 HA12412 1.55 4585 1.00 1..M30 144 0 30 51.6.24C 3.28 LF 13741 0.33 4010 0.30 4071 0.22 7472 0.27 74143 2.50 74197 0.55 7410 0.49 74123 0.55 74197 0.65 7414 0.55 8 F 367 49P 4702 4.50 7473 0.28 74144 2.50 7420 M3011TC 065 511625P 2.17 0447656044 0.80 4011 0.24 4072 0.22 74198 0.85 7415 0.14 74124 1.80 74200 3.45 0.70 86395 18p 0703 4.48 7474 0.78 70145 151324 064 011626P 2.44 4011 0.15 4073 0.22 0.75 74199 1.00 7420 0.13 74125 0.29 74202 3.45 7430 0.20 8E479 66P FREO. DISPLAY 4704 4.24 7475 0,35 74147 1.50 74221 060 11(1339N 066 S11630P 182 4012 0.20 4075 0.18 74221 1.00 7421 0.15 74126 0.29 7432 0.20 11F6795 550 AND SYNTH 4705 4.24 7476 0.30 74148 1.09 74740 099 7442 15.134844 1.86 SL 1640P 1.89 4013 0.35 4076 0.60 74246 1.50 7472 0.15 74132 0.45 0,80 864104 I 33 DEVICES 4706 4.50 7480 0.26 74150 0.79 7426 0.18 7448 L F 3515 0.49 01.1641P 1.89 4015 0.70 4077 0.23 74247 1.51 74133 0.30 74241 0.99 1.03 BFW92 600 4720 4.00 7481 0.20 74151 0.55 74242 1.65 7473 L F3535 076. TDA2002 1.25 SAA1056 3.75 4016 0.30 4078 0.26 74248 1.89 7427 0.14 74136 0.25 0.50 0E195 99P 0723 0.95 7482 0.75 74153 0.55 74243 1.65 7474 LA13745 3.75 015224216 3.05 SAAI058 3.35 4017 0.65 4082 0.25 74249 189, 7478 0.35 74138 0.40 0.50 OFV90 900 4724 0.95 7483 0.60 74154 74139 0.40 74744 0.83 7476 40238 851. 11.13805•14 I 00 U14422838 100 5441059 3.35 4019 0.38 4093 0.45 0.55 74251 1.05 7430 013 0.48 4 25 2.24 7485 0.75 74155 0.55 74245 1.50 7483 L.A1380N 8 1 00 CA3080E 0.70 11C9ODC 14.00 4020 0.68 4099 0.99 74265 0.66 7432 0.14 74145 1.20 0.98 13E256 38P 40014 0.54 7486 0.24 74156 7433 0.16 74147 2.10 74747 1.35 7485 098 LA13815 181. CA3089( 1.84 151232 19.00 4021 0.75 4175 1.15 ass 74273 267 75655 281 , 40085 0.99 7489 1.05 74157 742.18 1.35 7486 0.26 116419CE 1 98 CA3090A0 3.35 LNI242 19.00 4022 0.68 4502 0.90 0.55 74278 249 7437 0.17 74148 1 .60 258168 35r. 40098 0.54 7490 7489 2.68 4405435 i.80 CA3123e 1.40 e/61.2318 3.84 4023 0.19 4503 0.55 0.30 74159 1.90 74279 089 7438 0.16 74161 0.35 74249 I.35 3310 691. 43106 0.54 7491 0.55 7490 0.80 5859544 0.30 CA3130E 080 M5M5523 11.30 4024 0.45 4506 015 74160 0.55 74283 1.30 7440 0.13 74153 0 .35 74251 0.46 3179 65e 40160 0.69 7492 035 74161 74253 046 7493 0.80 NE556 0.50 CA31301 0.90 sisms524 11.30 4025 0.18 4507 0.45 ass 74284 3.50 7442 0,40 74154 0.99 40823 65i, 40161 0.69 7493 0.35 74162 14257 0.55 7495 0.94 NE5605 3.50 CA31401 0.46 riashiss25 7 85 4026 1.05 4508 1.99 0.55 47285 3.50 7447 0.42 74155 0 .50 40673 3.51( 51 40162 0.69 7494 7410/ 0.48 565625 4.05 CA31896 2.20 M5515526 7.85 4028 0.60 4510 0.70 0.70 74163 0.55 74290 1.00 7448 0.65 74156 0,50 74258 0,311 35845 490 40163 0.69 7495 0.60 5656444 4.29 CA3240 1.27 11.15615527 9.75 4029 0.75 4511 0.85 74164 0.56 74293 1 05 7449 0.61 74157 0.36 74259 0 39 74151 1.52 35851 540 40174 0.69 0.115 NE5655 1.00 1.1C3357P 2 85 5454405274 9.75 4030 0.35 4512 0.70 7496 74165 0.55 74297 2.36 7451 014 74158 0.40 74260 0.70 74154 2.26 35860 581. 40175 0.69 7497 1.40 0.24 7415: 1.52 NE5665 1.60 1539005 0.60 M512312 3.94 4035 0.75 4514 2.20 74166 0.70 74298 1 85 7454 0.15 74160 0 .40 vavim 351(88 1.24 40192 0.75 74100 1.10 4465705 386 153909N 0.68 0 89620 3.85 4040 0.68 4515 2.50 74167 1.25 74365 0.85 7455 0.15 74161 0.40 74273 0.90 74160 0.80 5E 5680 750 40193 0.75 74104 0.62 74161 0.80 51624 3 28 LM39145 2.80 SP8647 6.00 4042 0.65 4516 0.75 74170 1.25 74366 0.85 7463 1.50 74162 0 .40 74275 3.20 06961 700 4043 0.68 40194 0.69 74105 0.62 74173 74162 0.80 TBA651 1.81 LM39155 2.80 95H9OPC 7.80 4518 0.75 1.10 74367 0.85 7473 0.21 74163 0.40 74279 0.35 11C237 8i. 40195 0.69 74107 0.26 74174 75 74164 0.50 74163 0.80 ..A70911C 0.64 8114400 0.80 14040551 2.45 4043 0.93 4520 0.80 a 74368 0 85 7474 0 18 74780 2.50 11C238 Ri, KB4406 0.60 14044015 4,45 4044 0.68 4521 2_36 74109 0.35 74175 0 75 74390 1.85 7475 0.28 74165 120 74283 0.44 74164 0.80 tuA709PC 046 8C239 01 , TUL 'N' 74110 054 74176 74166 1.75 74165 0.84 ..A710/1C 0.65 884412 195 14012009 6.00 4946 0.69 4522 1.49 0.75 74393 1 85 7476 0.22 74290 0.58 (IC307 4047 0.69 74111 0.75 74490 I 85 7478 0.24 74168 0.85 74173 0.72 uA710PC 059 884413 1.95 HI344752 8.00 4527 0.95 '7400 0 10 74293 1.30 BC308 8r. 4049 0.30 74112 1.70 74178 0.90 74169 0.85 74174 0.72 ...A741C11 0.66 8B4417 1.80 MC145151 17,45 4528 0.95 7401 0.10 7483 0.50 74795 1.50 BC309 74166 1.98 74179 1.35 74170 1.85 74175 0.72 uA741CN 0.27 8844208 1.09 MC145156 8.75 4050 0.30 9529 1.40 7402 0.10 *LPSN' 7485 070. 74798 1.50 1177413 10$1 74118 0.85 74180 uA747CN 0.70 TDA44213 265 4051 0.65 4539 1.10 7403 0.11 0,75 7486 018. 74173 0.75 74365 0.35 4192 0.80 BC414 111. M1SC 74119 1.20 74181 7400 0.11 ...1.748C5 0.36 1(114423 2.30 4057 0.69 4549 3.50 7404 0.12 1 22 7490 0.37 74174 0.55 74366 6.35 4193 000 E1C415 100 ICM7106CP 9.55 74120 7401 011 ..A753 244 KB4424 1.65 4053 0.69 4554 1.73 7405 0.12 0.95 74197 0.70 7491 1.25 74175 0.55 74367 0.3 /4195 0.80 8C416 1 1 0 ICM7107CP 9.55 74121 0.35 74184 1402 0 12 74481 135 74200 4.52 uA758 2.35 KB4431 1.95 4054 1.10 4555 0.72 7406 0.22 1 20 7492 0.39 74368 035 BC546 170 ICM721613P 1950 4055 1.30 74122 0.34 74185 1.20 7403 0 12 /4183 2.96 74221 1 06 T8A820M 0.78 864432 1.95 4556 0.58 7407 0.22 7493 038 74373 0.78 00556 12p ICM7555 0.94 74123 0.40 74188 100 7404 6 13 74189 74901 0.38 TCA940E 1.80 884433 1.52 4056 1.35 4 • 74374 0.78 EIC1.50 74902 0.38 17P TOA1028 2.11 1(04436 2.53 74375 1.15 120 CRYSTALS CRYSTALS RADIO CONTR OL ALL PRICES EXCLUDE VAT - CURRENTLY AT 15% 74903 0.38 TOA I029 2.11 804437 1.75 74377 1.99 BC639 720 2.7. T0111054 1.45 8 04438 722 0514, 2.70 10.245 2.00 OC SUAIS POSTAGE 50p ORDERS UNDER £12 • FREE OVER £12 74378 140. 74904 0.38 BC640 220 100514, 385 2.50 TOA1062 1.95 884441 1.35 10.6985 AM T X11.1X 74379 215 74905 5.64 2SC1775 180 45514144 5.00 10.700 2.00 TDA1072 2,69 854445 1.29 FM RX. 74384 7.50 74906 0.30 20.11.872A 140 1 0008111, 795 10 7015 2.50 1(341074A 5.04 884448 2.75 3rd ot/30pF The lowest prices for prime. repealable devices We think 74385 4.20 74907 0.28 25066611 3(5e 3.2768 11 00 2.00 TOA1083 1.95 1(84448 1.65 2.70 HC250 1.65 74386 0.29 74908 0.11.4 2S1.16464 30, 4.000 2.00 11.115 2.00 so, and wait to hear 10 the contrary Ambo's new bigger, TOA1090 3.05 44650445 2.26 FMT X Fund 74390 asa /4909 1.52 260868A 40p 4.1934 200 11 520 2.00 HA1137 1.20 NE55325 1.85 20pF HC25U cheaper and complete range of parts covered in our new 74393 0.61 74910 3.62 750648A 4111, 4.096 1041 74395 210. HA1196 2.00 506000 3.75 hag 1.85 74919 0.86 750760 451 , 4.032 2.00 12 page A4 formal short.form and Price 1.11 available free HAI 197 1.00 S1.6270 2.03 9 0015 2.00 PAIRS ,AM 310 74396 199 74918 098 7013720 4.433619 with an SAE. and supplied wilh all orders. TOA1220 1.40 516310 2,03 2.00 21.000 ZOO You can order 74398 2.75 74925 4.32 25C2547 19p 4.800 7.00 24.000 2.00 PAIRS, FM 3 25 151303 0.99 516600 3.75 by ACCESS/BARCLAYCARD, cheque, PO with order or 74399 2.30 74926 432 7041085 200 5.000 2.00 CHANNELLING 0111307 1.65 016640 2.75 25.000 2.00 74445 1.40 743127 432 2511153 2.34 6 5536 come into our refurbished retail shop and use 'real* money' MCI310P 1.90 516440 POA 2.00 26.000 2.00 275117 501.15 74447 1.95 750723 7.34 MC 4330 1.20 516690 3.20 7.000 2.00 18.000 7.50 35510 201.14, Our 3 catalogues (E1.85 one. or 75p ea rm.) cover the 74490 1.10 706134 310 7.68 2.00 MC1350 1.20 516700 2.35 SIAL FILTERS BIGGEST RA NGE OF RF components in Europe as well 74668 1 05 EROE 70149 3.10 11111370 1.90 1CL8038CC 4.50 8.000 7.00 1010401 10.75117/, 1581H BW, 74669 1.05 today The saving you 208135 4.25 HAI 388 2.75 54569362 1.75 9.000 2.00 8 pole. 14.50 as standard parts, so invest a set 74570 170. 25E50 4.25 10 000 2.00 Subjecl to TOA1490 1.96 M5t9363 1 75 1010220, 10.7 Mhr, 2.485, B M make on your first couple orders writ soon repay th cost. 258227 3.55 10.240 2.00 MC1496P 1 25 14411211 1.95 588 8 Pole. 17.20 21083 .1 TELEPHONE (STD 0277) 230909 TELEX 995194 AMBIT G POSTCODE CM14 4SG [11111BIT international 200 forth 5eruice Rood, Brentwood, Essen

J. BIRKETF 25 THE STRAIT, LINCOLN Tel: 20767 SILICONIX ANALOG SWITCH 2XSPST TYPE DG 182BA @ £1.30. SPECIAL CRYSTAL FILTERS SE 1 OCI I I2V 1-4MHz 6W. 3-2kHz; S6I 0C11122 1.4MHz BW. 3.2kHz: SE1 0C1512U, 1.4MHz; BW, 10kHz; SE1 OC15120 1.4MHz BW, 8kHz: CRYSTAL ELECTRONICS F00138 1-4MHz 8W, 5.7kHz; FILTECH ARA 1007 1- 550kHz; all filters at £5 each GEC 0C1207A I-6MHz BW, 13kHz; GEC OC 1207C 1.6MHz BW. 3kHz: both £7.50 each. CRYSTAL ELECTRONICS F00035 BD41112, 13 1325Hz @ f7.50 each.

B7G GLASS CRYSTALS 99 , 730kHz with base @ £1.30. MINIATURE CERA MIC TRIM MERS 2-5, to 6p1, 3 to 10p1, 4.7 to 2091, 610 35pf, 10 In

40pf, 10 to 60pf; all at 15P each. UHF 3 PORT CIRCULATORS TYPE PGA 3642 890 to 960MHz @ £17.50. TANTALU M TUBULAR CAPACITORS 4- 7uf. 10VW @ 6 for 25p. SPECIAL BFY 90 IN STRIPLINE FORM @ £1 oaCh. FERRITE BEADS FX1115 @ 15p doz; :" type, 6 for 10p. MINIATURE WIRE ENDED RF. CHOKES 10UH, 33UH, 330UH: all 7p each SOLDER•IN FEED THRU CAPACITORS 6-8, 27. 300. 1CK1Opf; all 20p doz VHF FET J304 @ 309, BF 258 @ 4 for 75p. HEWLETT PACKARD HOT CARRIER DIODES 5082 2800 @ 40p. SUB-MINIATURE COIL FOR MERS with core dia 4mm. Len 9mm Ea 7p. DX MEWS POWER FETS VKlOKM @ 40p each SOLID SILVER WIRE ENDED AERIAL SWITCHING PIN DIODES with clICUIIS @ 40p each Z3CM. 3 PORT CIRCULATORS TYPE NGA 3642 @ £17.50. DX NEWS-SHEET has been published since 1962, MINIATURE 100 PIV 10 AMP BRIDGES @ 95p each. and is available world-wide. It contains up-to-date SPECIAL OFFER OF SURFACE ACOUSTIC WAVE (SA W) BANDPASS FILTERS Type 37 10.7MHz. bandwidth 330kHz, Will) data; typo 31, 63•5MHz. bandwidth 274kHz with data. information on DX stations currently active, full both at £16.50. QSL addresses, details of forthcoming MULLARD SUB-MINIATURE DISCS 1000pf 63VW @ 25p zloz DXpeditions, Contests, new Awards, DXCC MINIATURE 100 PIV 10 AMP BRIDGES @ 95p. TRANSISTORS SIMILAR TO BFY 90 @ 3 or £1. matters, daily propagation forecast, and also HFC 600 8 DIGIT FREQUENCY COUNTERS 1600MHz1@ OM. enables you to keep your Prefix List up-to-date. VARIABLE CAPACITORS 10 r 10 10pf @ 754. DISC CERA MICS 0- lul 18VW, 0- 22uf 6VW. 0.5uf I2VW. all 6p each. Items are arranged in alphabetical order for easy LINEAR MICRO WAVE TRANSISTORS 250m W al 2GHz max freq. 5Gfix with data £3 reference. It is mailed each Wednesday. each. LINEAR MICRO WAVE TRANSISTORS 500m W at 20H: max freq. 5GHz wah dala @ Apply to RSGB HQ for a subscription application £4.50 each. GENERAL PURPOSE MICRO WAVE NPN TRANSISTORS 5GHz 83m W at 2GHz with form. data @ £2.50. MICRO WAVE TRANSISTOR 5GHz 150m W ai 2GHz wigh data @ £3.50. 80 METRE CRYSTALS 10X type 3642-5kHz; 3750kHz; both 40p each. X BAND GUNN DIODES with data @ f1.65

Please add 30p for post and packing. Orders over £3 post free.

574 RADIO COMMUNICATION June 1981 4JRD,TE, G8SYG f?,A EAST LONDON HAM STORE DAVE

191 FRANCIS ROAD LEYTON E.10 H. LEXTON LIMITED TEL 01-558 0854 TELEX 8953609 LEXTON G RADIO Et ELECTRONIC ENGINEERS ENGINEERS ALWAYS AVAILABLE ON THE PREMISES MAIN (UK) SERVICE CONTRACTOR TO HITACHI SALES (UK) LTD

EXCLUSIVE TO US IN THE UK. lkW input 600W ssb 350FM 2MTR LINEAR!!

BUILT-IN POWER SUPPLY, ELECTRONIC WAR M UP. VARIABLE INPUT ATTENUATOR. ADAPTS EXCITERS FROM 2W 25W. RADIAL BLO WER. LED's FOR READY. TX, OVERLOAD. PTT Et RF VOX WITH VARIABLE DELAY CHOICE OF EIMAC TUBES. 4 x 150A OR 4C x 2608 OR 4C 25OR ELECTRONIC PLATE CURRENT FUSE- NO THER MAL DAMAGE OF P.A. TUBE POSSIBLE. SIZE: H88m m, W.318m m, D.375m m. FROM £460.000

ICOM ICOM MULTIMODES ICOM FM MOBILES ICOM 720A G/C PORTABLES - - IC2E FM 2m _ - .. ' - 1 :4.9•:- '....' :«; 111111 -01 ,.,,, ft . £159.00 1 .'..;-_ - -.....r,.... - IC202 SSS _. _. „,..:-..-: , £169.00 ---).). - - -)ti-e-",),. 0 ':. IC402 70cm à -. -, ,' . 'i' -: ': ;...... -P '' ‘1 *- • , ,.-+-..e.r \,. £242.00 All accessories available IC251 2m NEW! IC249 £199.00 IC720A 1 IC260IC451 2m70cm E579.00E479.00 IC240 IC2KL 500W Linear TBA IC255 £169.00 Auto Mobile Mount £796.00 (339.00 E255.00 TBA

C e I C O M , WE ARE PROUD TO ANNOUNCE THAT WE ARE AUTHORISED DEALERS

ICOM YAESU/SOMMERKAMP MICROWAVE MODULES ROTATORS IIS PORTABLES M MA 144V Pre-amp £34.90 DR7600X £130.00 MML 144/25 RF amp £59.00 DR7600 £14 5.00 IC2E 2m £159.00 FT707 'Wayfarer Yaesu £525.00 IC202S 2m £169.00 MML 144/40 £77.00 DIA WA I C402S 70cm £242.00 FP707 Power supply £109.00 M MT 432/144 2 70 DR 7 500R £105.00 transverter £184.00 IC1OL 10W IC 2A TBA FT767D Sommerkamp DR7500X £95.00 MMT 144/28 10 2 DIAWA MOBILE cw filter Et- mic £559.00 IC240 £169.00 transverter £99.00 K R400 £105.00 FT101ZD WARC Yaesu £569.00 IC249 New synthesised £255.00 M MT 28/144 • HAM IV £145.130 IC260 Multimode £339.00 FT101ZD Sommerkamp M ML 144/100 10 in, 100 out CHANNEL MASTER BASE/MOBILE digital + WARC + option £649.00 mic pre-amp £142.60 9502 55.00 IC251 2m £479.03 M MD 050/500 counter 101Z0 MkIll Yaesu FM £599.00 IC451 70cm £579.00 0.050-500MHz HF FT225RD £540.00 Full range stocked SWAN/CUBIC IC730 HF 200W PEP TBA FT207 2m portable £196.00 100MX 235W £375 00 IC720A 100kHz 30kHz general FT48OR Multimode 2m £359.00 102BX 235W - PS5 [800 00 coverage -i• Transmit on all bands STANDARD TS280LP 10W Mobile 103BX WARC 235W f810 00 for commercial purpose Was Twins, now Triplets PS6 Power Supply (145.00 IC5PS Power supply £100.00 Sommerkamp £159.00 C8800 2m £250.00 C7800 70cm £270.00 150MX Digital £561.00 IC2KL £900.00 TS280 FM 50W Mobile All accessories for ICOM C78 70cm Portable £209.00 15002 Linear £406 00 Sommerkamp £199.00 ST2A ATU TBA available CM8 Mobile Cradle £17.00 F1725 VHF Mobile CPB78 Linear £65.00 ST3A ATU TBA HF Mobile ant £80.00 TRIO/KENWOOD Sommerkamp £240.00 Special Astro 102BF £600.00 TS830S HF Transceiver £625.00 TS130S HF Transceiver £490.00 CUSHCRAFT AMATEUR ANTENNA TS2300 2m Portable £165.00 HF. A3 20/15/10 3 ele beam 214B 14 ele boomer 15.2d8 £49.50 ARB2K Conversion kit £12.75 Car-Tray + 10W amp £65.00 8dB E147.00 ARX 2 Ringo Ranger 6c1B RINGO Mk1 to Ringo Mk11 T R13400 UHF mobile £275.00 ATV3 20.15.10 Trapped Vertical £24.75 TR7800 VHF mobile £265.00 vertical £34.00 CS100 Communication FULL RANGE AT130 (72.00 ATV4 10.15.20.40 Trapped Speaker £12.50 IN STOCK AS30 £85.00 vertical £68.00 A144• 4 4 ele Yagi £16.25 CATALOGUE 21000 general coverage ATV5 10.15.20.40.80 Trapped A144 • 7 7 ele Yagi £20.31 AVAILABLE receiver £285.00 vertical £74.00 A144- 11 11 ele Yagi £25.72 SAE PLEASE Many Trio/Kenwood accessories VHF A3219 19 ele boomer DX120 20 ele Yagi £47.20

1111 11 available 16.2d8 £62.00 AR X2B Ringo Ml<11 £28.75 /If ALL ACCESSORIES AVAILABLE-PLUGS SKTS CO-AX 2MTR COLINEAR £31.50, 70CM COLINEAR £31.50 Access PRICES INCLUDE VAT AT THE PRESENT RATE OF 15% BARCLAYCARD OPEN MON FRIDAY 9:00-5:30. SATURDAY 10:00-4:00. INSTANT HP FACILITY AVAILABLE Atgl EASY ACCESS M2-M11-M1 NORTH CIRCULAR ROAD-EASY PARKING

RADIO CO M MUNICATION June 1981 575 muTek limited rf technology from G4DGU

PLEASE REMEMBER: If you intend to spend a holiday in Devon or Cornwall and feel that THE CO. CENTRE you'd like to visit us, may we ask you to remember that we're not an 10 Merton Park Parade, Kingston Road SW19. amateur radio shopl We're not set-up to deal with casual visitors, and we do ask potential custo mers to telephone first. We will be running 'open (Nr. Nelson Hospital) 01-543 5150 mornings' most Sundays, and we hope that most people will wish to come to these. LONDON'S NEWEST Et BRIGHTEST EMPORIU M

We are, as ever, happy to welco me all A mateurs and Short-Wave Ne w Products Listeners to London's newest emporiu m. FT101 front-end board This board is the first half of a two board set intended to do for the FT101 loot ZDs) what our highly successful FT221/225 board has done for that transceiver. The first board IFT101GTA) Come along and see our wide range of new and s hand equipment including replaces PB-1181 and puts a properly terminated schottky diode ring mixer into the receiver Standard -- Yaesu -FDK -Trio- Azden- Cushcraft, Micro wave Modules, signal path with other refinements such as an improved bandpass filter at the second etc. We can supply and fut the well.known Mutek Products and we have a Itunablel if. The second board (FT101G7131 which we expect to have available by September replaces PI31180 using a high-level ring mixer feeding an additional 3180kHz crystal filter. varied selection tul antennas and accessories. FT101GTA - £29.83 Many stations are now using the HBSCV 2-element 2m beam, (8.50 inc VAT. 144MHz switched preamp This is ideal for portable use or where limitations exist to the use of outside We've never been particularly sold on the idea of rf switched preamps, however the demand for a good reliable design is rather high and so we've succumbed! Essentially we've taken our aerials We are Sole London Agents for the 1-1139CV and welcome trade very successful 144MHz Ina design and grafted-on a reasonably sophisticated 2-relay enquiries. changeover circuit which may be operated either by incident ri or by hard switching line. In the rf 'switched' mode the power handling capability is in excess of 100W, whilst by using property sequenced 'hard switching* this can be doubled. An environmental enclosure to IP65 We will part exchange new or used equipment and are keen to buy s/hand items is available for masthead rnountino. at fair prices, working or faulty. We will also display and sell your equipment on Unboxed - (18.27 Boxed - £24.85 Environmental cased - £31.39 a com mission basis. 144MHz halo antenna In the days of am, the "orrib1e 'ale' was the standard 2m mobile antenna. The growth of ver- We have just obtained dealership for the G.M.T.C. Answerphone Machine. tically polarised fm land probably the negative aesthetics of the commercially available This is nationally advertised and is excellent value at £123.25 + V.A.T. I less than designI caused it to fall from favour. The availability of mobile multimode boxes has led to an increase in ssb mobile activity which we suspect is proving rather disappointing to those peo- a year's rental with other makes). This machine is, of course, G.P.O. approved. ple using vertical whips. Our halo is an optimum 2m ssb mobile antenna which mounts on the gutter of most cars using a cast aluminium clamp. It may be easily detached for parking etc If you are unable to call in for coffee and a chat then please ring us- we are and is well made from materials such as stainless steel and quality alloy and will handle (at always ready to discuss your needs and problems. As a goodwill gesture we will least). legal limited motoring and 200W pep of rf - deliver most items, same day, free of charge anywhere in the Greater London Other products area. FT221/225GT Front-end board With numbers of this board around, we suspect that it probably doesn't need too much Looking forward to meeting you, 73's de Bob, Ian, Paul. advertising. Suffice to say that three out of four certificate winners in the 144MHz fixed contest were using this design! - 53.87 Late nights Wednesdays and Fridays till 8

1.3GHz Ina Very high performance and a very low price from a property engineered microstripline design. Unboxed - E26.13 Boxed - £35.40 1-3GHz receive converter EUROVER ELECTRONICS This was our very first product: we still make it although we haven't advertised it very widely of late. It offers 8d8 ssb noise figure with a highly stable local oscillator chain using 5ppm COAX UR67/RG213 50 ohms, 113.3mm. 51p/m 15p ;nt -Et min.! 60m max. by post. crystal. We only sell it as a board as it is intended for use with our other system UR76/RG58 50 ohms, 4-95mm. 21p/rn 13p/m - 50p min.1 components: - f22.00 VALVES 64J8 -(1.60: 6BM8-11.30: 6EH5 -€1.80: 6HS8 -f2.90; 12AX7A-E1.40 6A05 -f1.65: 681‘18 -f2.26: 6EJ7 - (1.68; 6J86A - f:2.90: 12BA6 -(1.40 The "Moonbeam"- 15 element 4-25 NBS yogi. 1-£16.50; 2 -f32.00: 4-(.63.03; 8-f 116.00. Carriage £3.00 per antenna 6AT6 -(1.50; 68V8 -E2.40; 6E58 -C2.95; 6JHB -f2.80; 12E1E6 -f1.55 6AU6A 6826 -(1.45; SEW -(1.80; 6JS6C -F2.50: 12BY7A -f1.66 144MHz preamp Boxed -£17.72 Unboxed-E10.79. 6AV6 -(1.30; 604 6EW6 -(1.65; 8KD6 -f3.75: 12826 -f2.95 6AV11 -(1.75: 6C10 -£2.15; 60E5 -E2.70; 6KE8 -(2.80; 12GN7 -f2.50 Kungsimport Antenna Combiners 6AWBA -(2.05: 60E16 -(1.65: 6GK6 -(1.95; 6L06 0A2 -f1.40 PliCOS and other details listed in previous ads. We now have Ben's dish feeds available at 6BA6 601,6 -f2.15: 6GM6 6MJ6 -(4.20; 6146A -(5.10 £30.00 for both the 1-3 and 2-3GHz versions: they realty are well made in brass and are fitted 6BA7 -(4.20; 6DC6 -£1.90; 68W8 -C OO: 6U8 -(1.80: 614613 -13.10 with an integral 'N' connector. 88E6 -(1.65: 6005 - O M; 6GX6 -(1.50; 12AT7 -f1.65: 5728 -C25.00 65J7 -(1.40; SEAS 8HF5 12AU7-(1.45; 7360 -I:9.20 TVI filter MLR f1.60: 6888 -f2.75; 8HFEI -(2.30: 12.AV6- (1.35; 8950 - f6.90 This is a bandpass filter covering the 470-860MHz band, synthesised using microstripline Ask for quote for other types. (P&P 20p each, free over £15) techniques. Many people have found it very useful in dealing with TV! from both hf and vhf transmitters.- £1.811. CONNS 50fIN Series 508BNC Series P1,2591S0239 Series Plug for UR67-(1.00: Plug for UR76-E13.63; PL259 special, UR67-£1.15 Data on request. SAE appreciated. CWO. Please add 50p pep unless otherwise stated. and Plug for UR76 - EO.97: 4-hole socket -(0.50: PL2E0 special. UR76-f1.98 then VAT. Tnxl Ski. for U867- 0.83; S0239 4-hole socket -E13.40 4-hole socket - f0.97; (All connectors 30pr order. free over £151 m uTek limited, Brad worthy, Hols worthy, N. Devon EX22 TTU Mail Orders please (P&P in brackets) but callers welcome by appointment. Telephone: Brad worthy (0409 24) 54,3 EUROVER LIMITED, Pietro« Close, Little Tatham. Malden, Essex CM9 BJN

SA MS ON ETM-3C KEYERS G 4 D S G D. P. HOBBS LTD. G3 HE O Professional grade C.MOS keyers built for dependable Marine Is Commercial use world-wide. Backed by Spacemark service. Only 1pA battery idling current) ETM-3C, £88.86 THE RADIO COMPONENT SPECIALIST PP1305 13-8VDC 4amp stab, power supplies, £18.40 E2.00 P&P. EWA 4C ItteitORT KETER- Has ETM 3C features plus 4 memories each taking aperos 22 Morse characters Iswitchable 4 x 256 or 2 512 bits). Erase/rewrite as often as needed. By just PP137 13.8VDC 7amp stab, power supplies, £2.00 +U.00 P&P. pressing a button it sends COs etc once only, or repeatedly, and at any chosen speed. £124.96 PS134 13-8VDC 4amp stab, power supplies, 123.00 +£2.00 P&P. AMMER PRECISION HAND KEY. 0117. 85.1151 SINGII MOOLE KEY MIT £13.85 DL20 Dummy Loads 15W 130W Pk). £6.04 + 35p P&P. fr A11010 PHASE SHIFT NETWORKS, octal based. HFC55 10kHz-55N1Hz, 5 Digit Frequency Counter, £36.50 + £1.50 P&P. All prices postpaid and include 15% VAT. Please send stamp with all enquiries. YVV3 Twin Meter SWR bridge 3-5-150MHz, E11.95 - 60p PEIP. FX1 Station VV/meter 700kHz -250MHz, C29.00 « £1.20 P&P. DM350 PTT Mics 50k. £4.83 +35p P&P. SPACEMARK LTD. Te ra Fg eMHO CUHSEESHCIFEel 0ef R92rAD i R517 Air Bend Monitor Rec. £49.75. SF19 2Mtr Mon Rec, £46.00. Electrolytic' ideal for Linears 403mfd 350V, £1.50 inc P&P. Yeesu FR07 Et Lowe SRX30 Receivers in stock. FDK 700EX Et 750E 2m. Transceivers in stock. VALVES VALVES VALVES ASCOT. BANTEX and JAYBEAM AERIALS, VERO Products, Alloy and Plastic Boxes, The following valves in matched pairs ILIS6/C. 610)6. 6J86/A, 6106, 6HF5, 614 M, 61488. Resistors, Capacitors, ICs. Transformers. etc. BERNARDS and R.S.G.B. Technical Books. YES the 6JS6/C is Japanese and works in the F7101. Most amateur radio valves including Prices Include VAT All MailÓrders to Luton Access/Barclaycard difficult to obtain types EX STOCK. Quotations without obligation. If we don't stock your tlfeo we may be able to import for you, PLEASE ENQUIRE. REMEMBER over 200 types EX 11 King Street, Luton, Beds. Tel, 20907 STOCK. Sae for list. 'Phone for assistance re types suitable for your equipment. USA and Jap manufacture of popular types available. Open 9 em -5.30 pm Mon Sat. Closed all day Wednesday DON'T DELAY 'PH ONE TODAY 0204 54165, G4AZ M Also visit D. P. Robin Norwich Ltd, 13 St Benetfict's St, Norwich, TeL 615786 Closed all day Thursday Wilson, 20 Croft Gate, Har wood, Bolton BL2 3JJ

576 RA DIO CO M M U NICA TIO N June 1981 STEPHENS-JA MES LIMITED

" TRIO R-1000

TRIO TS-130S TRIO TS-830S " am

AT130 £72.89 AT230 £106.72 TA 8400 £279.00 TR7800 £268.00 TRIO PRICES TS830S £639.52 TS 120V £347.30 DM801 £51.75 T R9000 £345.00 Full Range of TS130S £491.00 TS130V £404.34 TL922 £595.70 R820 £690.00 Accessories Available TR2300 £166.75 TR2400 £198.95 TS770E £730.25 TS180S £679.60 PS30 £85.00 TS530S £40.00 VB2300 £49.45 PS10 £63.00

DAIWA Full range of reliable NRD-515 RECEIVER antenna rotators DAIWA ANTENNA TUNER

e mpg,

For the discerning DXER comes the modern NRD-515 general coverage receiver • Full of all performance advantages offered by YAESU R512 Aucrelt Bend Scanning Receiver 1138.00 any receiver fib All modes of operation PLL Digital VEO S Solid F RG7 Receiver £189.00 Digital Flight Scan Airband Receiver £230.00 state • Up conversion type double conversion rie Frequency DRAKE SRS 2m FM Receiver £46.00 coverage 100kHz to 30MHz • LF/MF bands below 1-6 MHz are 1117 Transceiver and AC PSU 11.242.00 FDK TM5613 FM Scanning Receiver 1109.00 MN7 Antenna Matching Unit £124.20 AMR217B 2m Scanning Receiver 1120.75 clearly receivable through the use of a filter/tuned circuit • Band Bearcat 220F8 Scanning Receiver G58.75 117 General coverage receiver £989.00 Pass tuning • Noise Blanker • AIR • Attentuator S AGC • Other Drake equipment available to order Standard ceeco FM Transceiver £252.00 AR22 2m Handheld Receiver £85.00 Recording terminal • Mute terminal, etc which permits operation S.T.E. MILAN SX200 Scanning Receiver £239.00 with the NSD-505 transmitter or ant transmitter • Optional: AA1 Audio Module £4.96 AR20 C C. FM Receiver PCB E45.00 HY-GAIN speaker, me mory unit. cw filter available. PRICE: £948.75 ¡tic VAT 12AVO 10 15 20m Vertical Antenna £43.13 JRC N50515 Transmitter. Matching una to the NRD515 Receiver available STABILISED POWER SUPPLIES 14VEP W13 10 15 20 40m Vertical £60.38 Model 12510 15V 5A 126.00 18AVT5WB 10 15 20 40 80m Vertical £87.40 shortly. 65 years of experience produces the finest "separates- available in the Model 1210/110A 13.5V E66.00 world to the Radio amateur who wants the best in Amateur Radio VARIOUS ANTENNA Model 156S 4 15V 6A Twn Mete, £40.00 HF5 venical 10-through 80m 141.40 Model 1210S 4 20V 10A Twin Meter 168.00 Shop Hours: Mon to Fri 9.30am to 5.30pm Discone 5 Antenna 50 486MHz £36.80 Model 1220 13- 5V 20A E95.00 C4X 10 15-20m Vertical £46.00 Saturday 9.30am to 4.30pm ACCESS and Barclaycard facilities Maximum ratings quoted HO-1 Minibeam Tribander £96.76 HP terms arranged. Part exchanges always welcome STATION ACCESSORIES I inc post1 Complete range of JAYBEA M HF AND VHF-UHF W e are located on the A574. Turn at Greyhound Motel on the SWR 25 Twin meter £12.80 Antennas. send 15p for catalogue and price list. the 2-way Antenna switch (V21 £6.50 G-WHIP. Mobile Antenna Range A590 (East Lancs Road) and we are about on right. No 3-way Antenna switch I V31 £10.80 Tribander Helical 10 15 20m C23.00 parking problems at any time. 4.way Antenna switch I V41 £11.00 LF Coils for above £6.56 2-way Antenna switch ivHFI E11.00 LF Telescopic for coils £3.00 DL50 50 watt dummy load 50ohrn £7.00 Standard Basernount £4.20 Oscerblock SWR2C08 SWR ( Power £41.00 MultiMobile 10 15 20m C26.45 STEPHENS-JA MES FX1 Station Wavemeter C29.00 Coils for above £6.56 Wellz S P200 swr., powe E4995 Extendarod E10.93 LIMITED Dahva CN620A £54.00 Flexiwhip 10m £16.00 Full range of aluminium tubing, wall clamps. Coils for above £6.56 47 WARRINGTON ROAD brackets "V - bolts for the caller FDK TRANSCEIVERS AND RECEIVERS Multi 700EX Transceiver £199.00 LEIGH WN7 3EA SR X30 Solid State Receiver £158.00 Multi 750 Transceiver £29000. ENGLAND Sky Ace aircraft band hand held receiver £49.00 Palm 2 Portable Transceiver £89.00 Telephone (0942) 676790

R A DIO CO M M U NIC A TIO N June 1981 577 1 RAILWAY ROAD, BLACKBURN, LANCS. Telephone: 51842 (Evenings: Bolton 592929 G4GHE) YOUR SOM MERKA MP IMPORTER

TS802 Handheld 80 ch 2m Transceiver with scanner. LED channel readout, tone burst, reverse repeater. 2 watts/0•2 watts output. See TS802 previous issues of "Radio Communication" for full spec. Complete with 12V charger. New low price, £129.

TS280FM Two versions of this popular model are now available. Both have 80 channels with auto repeater offset Complete with mobile mount and microphone - and, of course, reverse Som merkemp's new FT48OR 2 metre multimode. Ideal base station/mobile rig with repeater. satellite offset facilities. Tunes 143-5 148'5MH r, 103MHz, lkHz. 12-Ski-b la 25kHz steps TS280 HIP with 50 watts/8 watts output, £199. Four memory channels may also be scanned. 30W pep. input on SSE and 30W DC on FM TS280 LIP with 10 wattsil watt output, £159. and CW. Complete with scanning microphone and mobile mount. £349. Matching power unit £49.

FT767DX Similar to FT707 with CW fitter and scanning microphone. £499 inc. VAT, Mains

Power unit. £106 II1C. VAT. FT227ZD Similar to FTIOIZD but includes cw filter. 12V converter. cooling fan and microphone - extras worth at least E95. £589. FT991DNI including such extras as AM and CW crystal filters, electronic hoyar, inbuilt AC and DC power supplies, microphone, frequency memory and cooling Ian, £795. FT307 Similar to FT107 with CW fitter, memory circuit. scanning microphone and AC/DC power supplies, (899. FRG7 0.5 30MHz receiver (188. FRG7700 HF receiver and memories £379. FT225RD Multimode 2 metre £495. FT207 FM hand portable transceiver £179. FT404 70cm handheld POA TS7880X 10 mtr, all mode 10/196W E325, We stock genuine Som merkamp quality accessories. NT3012V 3A regulated power supply, £23. NT60 12V 3A regulated power supply, E39. VS200 SWR bridge is power meter, reads 200W output from 1.8 150fv1Hz. £54. ALL PRICES INCLU DE VAT ACCESS Er BARCLAYCAR D Y52000 SVVR bridge is power meter. reads 2kW output from 1.8 60MHz. £72. HP TER MS AV AILABLE PART EXC H AN GE WELC O ME D

GM3OP W a m % GM4IPS JAYCEE ELECTRONICS 20 WOODSIDE WAY, GLENROTHES, FIFE, KY7 5DF Phone: 0592 756962/754918 Telex: 727181 OPEN 5 DAYS: TUES-SAT, 9am-5pm

* YOUR APPROVED DEALER IN SCOTLAND

PART EXCHANGE AND HIRE PURCHASE QUALITY, GUARANTEED SECONDHAND EQUIP MENT IN STOCK

COME AND VISIT OUR SHO WROO M AND TRY THE LATEST TRIO GOODIES HAVE A FRIENDLY CHAT WITH JOHN, GM3OP W OR GEORGE, GM41PS

HEAR GEORGE ON THE AIR OPERATING HIS TS830S

RSGB PUBLICATIONS LIST ON PAGE 584 RETURNS! UNDER THE PERSONAL DIRECTORSHIP OF ROWLEY SHEARS G8KW KW COM MUNICATIONS LTD. VANGUARD WORKS, JENKINS DALE. 2 70 23 CHATHAM, KENT, ME4 5RT CUT YOUR LOSSES! BY THE USE OF: • High Throughput Ilk SSB) Mast Head Preamps For 144 & 432MHz Very Low Noise Fig. & Excellent Strong Signal Handling Performance G2BAR HAM BAND AERIALS • GaAs Fet Preamps, NF © 1296MHz 0.5dB, @ 144 & 432MHz 0-4c1B Typ • Transverters (Low Noise, Ring Mixers Etc)- KITS -213- 144 -432 - 1296 10-15-20m MONOBAND YAGI BEA MS Full catalogue of all the SSB Electronic IW.GER MANY) range 302. 2-element and 3-element with GAM MA MATCH complete from £32.20 to £65.50 inc. VAT. PIPER COM MUNICATIONS For details and price lists send 30p stamps. 4 Severn Road, Chilton, Didcot, Oxon OX11 OPW UPPINGTON TELE-RADIO (Bristol) LTD 12-14 Pennywell Road, Bristol BS5 OTJ. Tel: 0272 557732 Telephone: (0235) 834328. Evening calls welco me.

578 RADIO COM MUNICATION June 1981 SOTA COM MUNICATION SYSTEMS LTD 22 26 CHILD WALL LANE, BOWRING PARK, LIVERPOOL L14 6TX, ENGLAND Tel: 051-480 5770 Hours 9am 6pm Monday to Friday Sam 1pm Saturday Telex: 628702 SOTA G

RADIO CONSULTANTS, SUPPLIERS AND MANUFACTURERS

BARCLAYCARD AMERICAN EXPRESS ACCESS

100 WATT 144MHz MOBILE LINEAR AMPLIFIER SCL 144

* 12V operation * Drive 10W * RF output 100W * Linear or Class C operation * Manual or RF keying

Price r100 + VAT (£115.001

100 WATT 144M Hz MOBILE LINEAR A MPLIFIER WITH BUILT IN PREA MP SCL 144P

* Linear specifications as SCL 144. LUNAR * Preamp * Gain 12dB W E ARE THE OFFICIAL IMP ORTERS AN D * N.F. <1-5dB DISTRIBUTORS FOR LUN AR EQUIP MENT Price £120.00+ VAT (r138.00) 2M10-80P linear £120 • VAT 2M3O• 160P linear £160 VAT PLEASE HF3-100L2 linear £120 VAT CONTACT PA28 preamp £20 VAT US PA144 preamp I:20+ VAT FOR PAI144 preamp £8 VAT FURTHER PA432 2 preamp £22 + VAT DETAILS PAE432•5 preamp !EM U (40+ VAT 'F RI 4:21

As a service to our customers we are now stock- ing Trio equipment. We do not claim to be an authorised Trio dealer, however we are confident that we can offer an effective spares and service back up.

TR-9000 2m Multimode £345.00 inc VAT TR-7800 2m FM mobile £268.00 inc VAT TR-2400 2m FM handheld £199.00 inc VAT

1,296MHz LINEAR TRANSVERTER PACKAGE DEALS TR-9000+ SCL 144PS £499.00 inc VAT * I.F. 28MHz or 144MHz

MZ-80K MICRO COMPUTER, PERIPHERALS AND SOFTWARE IN STOCK STOCK IN SOFTWARE AND PERIPHERALS COMPUTER, MICRO MZ-80K TR-7800 2m30- 160P £425.00 inc VAT * 12V operation * Drive 5mW to 500mW * RF output 2-5 W to 3W AERIAL ROTATORS * RX NF <3-5dB Sky King SU400 (inc top Er bottom clamps) £86.25 inc VAT Sky King SU2000 £36.80 inc VAT Price (140• 00 •- VAT 1E161.001

SAE WITH ALL ENQUIRIES PLEASE TRADE AND EXPORT ENQUIRIES WELCO ME

WE ARE NORTHERN REPRESENTATIVE FOR "VHF COM MUNICATIONS" MAGAZINES Ft KITS

TELEPHONE CREDIT CARD ORDERS TAKEN CARRIAGE OR POSTAGE FREE ON ALL EQUIPMENT

RADIO COM MUNICATION June 1981 579 Receivers Transceivers Fro m the World-Record JOYSTICK people! A REVOLUTIONARY STOP PRESS!! ANTENNA THEY CALLED CASH SAVING DEALS "IMPOSSIBLE" FOR YAESU GEAR THE JOYFRAME (Patent Applied for) PARTRIDGE "DIAL-A-QUOTE" SERVICE FRG/Rx's FT/Tx's. with, TVI-proof antennas if required, some FREE Amateur Bands, TVI-proof 3.5 30MHz, incl "new" offers with Rx deals. While you waited for this ad, PRICES HAVE bands. SW BC reception. PLUS 2 METRES!! FALLEN! We claim we're LOWEST) REME MBER it takes 2 MONTHS to The small package antenna for the pour OTH, that measures 23 , 23 , 23 get ads updated. BUT you can PHONE US NO W for your QUOTE) SAVE (inches) and just stands on top of the gear in shack' Directive on 80, acts as ver- TIME AS WELL AS MONEY! 0843 62535 iext 6) or 62839 after office hours. tical on higher freqs., many BC stns. G2VF with 30 watts has enjoyed world- wide OSOs. Incredible low-angle radiation! Rotated by hand, two knob tuning. TRANSMISSION, particularly with respect to size and freq. range, by SUCH A JUST TELEPHONE YOUR CARD NUMBER 0843 62535 text 6/. After office SMALL UNIT, has-we believe-been generally thought IMPOSSIBLE. It has hours 0843 62839 or send 14p stamp for FREE literature. Prices correct as al taken Partridge expertise, that produced the JOYSTICK, etc., to prove other- press. NOTE our prices are always INCLUSIVE OF VAT, carriage. Prompt ser- wise and to bring you another efficient, compact, substantially harmonic free vice too, goods usually despatched WITHIN 48 HOURS complement to your hobby. BARCLAYCARD COMPLETE JOYFRA ME IReceive only) £60.00 6. Partridge House. NSA Prospect Road. Broadstalrs, Kent CTIOILD COMPLETE JOYFRA ME (TX/RX) £110.00 Mailers by appointment) (Write- 14p -or phone for literature) Enquiries invited from outside the Amateur Service; an ideal prospect for all authorised stations. We can also advise on the installation of your VHF business le radio. rR04,0571710S III If f rn/MAYO 2 METRE PERFORMANCE. During recent opening. FM 050's Western Europe LEE-M ON K G3CED and Western G proved JOYFRA ME as super vertical for this band, INDOOR OPERATION!

NORTHERN COM MUNICATIONS FDK \e/ AMATEUR * COM MERCIAL * MARINE yAlsuYAESU • FDK • AZOEN DENTRON • STANDARD 41 JAYBÙIM • NAG • ASP • SWAN 40 &WHIP • MM • CDE S SEM

IMPORTANT NOTICE CUSHCRAFT Power Et Performance ANTENNAS We are proud to announce the official completion of our New Sales and Arv3 Vertical 10,15 , 20 lb) £34.00 Service facilities. ATV5 Vertical 80.)10m Ibl £74.00 Come and see for yourself the finest names in Amateur Radio equip' A144/7 7-element 10.5dB Vagi 144MHz la) £24.95 ment, including YAESU FR7700 RX, FT480R, FT780, the fabulous FT107M. A144/11 11-element 13dB Vagi 144MHz lb) £27.85 FT101ZD end super F1707 HF ranges. The Swan Cubic 100MX special of- 214B 14-element 15dB long Vagi 144MHz lc) £49.50 fer. the unique Astro 150 and now the revolutionary 103BX. A3219 19-element "Boomer" 16.5dB long Vagi 144MHz lc) £2.00 We will also be delighted to show you much more including AR X2 Ringo Ranger 6dB Vertical 144MHz la) £24.75 STANDARD'S C7800, C8800 and the delightful C78: FDK's good value AR10 Ringo vertical 10 metres lb) £22.00 Multi 700EX, M750E Multimode and accessories. Or how about the Bear- A10/3 3-element Vagi 7.6dB 10 metres 03) £52.00 cat 220 or SX.200A scanners at special prices? A15/3 3-element Yagi 7.6dB 15 metres lb) £72.00 Cushcraft is a main distribution line. Have you seen the new Ringo A20/3 3-element Vagi 7.6d8 20 metres lc) £139.75 Ranger conversion kit, to Ringo 2 spec? (f12.75) Excellent stocks of A3 3-band HF Vagi 8dB 10/15/20 metres Ipoa) £147.00 Antennas and accessories by famous makers. ZL12 -our very own 2 metre SPECIAL element Customer satisfaction is what we aim for, so looking, buying, or just nat- tering- why not try it our way? You may be in for a pleasant surprise! ZL12 13dB gain, 10' 6" long. Split boom la) £28.75 WIDE BAND ANTENNA- NORCONE ZL8 Compact 2 metre SPECIAL ele ment The new NORCONE DISC 512 is a wide band unity gain antenna, specially 2ZL8 9dB gain, only 6' 0" long. Split boom lal £17.95 developed for coverage of 66MHz 512MHz. An ideal partner for the BEARCAT Prices Include VAT, 'carnage extra. fat £2.00 lb) [100 let (3.75 SX200N and other scanning monitor receivers. It may also be used for transmis- sion; full coverage of 70, 144 and 432MHz amateur bands and aircraft, marine SPECIAL OFFER and public services. (al £24.95 SX200N - Norcone 512 complete inc VAT £286.00

BARCLAYCARD :t‘ 299/303 CLAREMOUNT ROAD, HALIFAX HX3 6AW, WEST YORKSHIRE VISA Ito, it with .1ircerr. Tuesday to Saturday inclusive 9.45am 5.30pm Telephone: (04221 40792-24-hour ans wering service G3UGF

TMP ELECTRONIC SUPPLIES G W3SSY Al Rcom of Abergavenny G W4EIN Stockist of Yaesu, Jaybea m, Hy-Gain, CDE, Swan, A midon THE FRIENDLY EMPORIU M IN A TOURIST TOWN Cores, KDK, FDK, Micro wave M odules, RSGB Books, ASP, Leader, Cushcraft, Daiwa, Dentron, Hansen. Plenty for the XYL to do while you browse in stock-rigs and accessories, microwave modules, Jaybeam, rotators, etc. Quad Spiders. Aluminium. . SEM Z Match 10 160m .£57 00 Low Pass Filters 2 30MHz . £19.50 TMI.'AFI Rings .£0.57 Shop open six days. Mail order. Access and Visa welco me. Balan Kits 3.5 21MHz...... [5.00 Copper Aerial Wire 70' £5.34 14 30MHz ...... £7.20 140' £8.84 22 Brecon Road, Abergavenny, Gwent NP7 5UG. 'Phone 2566

Trio R1000 Receiver £ZE(5 SRX-30 £158 FRG-7000 £259 FRG•7700 £309 FRG-7 £199 FRG-7D £230 SR 92m £46 ANTI-T.V.I, TRAP DIPOLES: SPECIAL OFFER FEW ONLY PNP COM MUNICATIONS S.W.L. Indoor models £14.50 Er £27.50 S W AN 100 MX TR A NSCEIVER 10 80m £365 inc. VAT S.W.L. Outdoor models £30.00 Er £36.00 "Universal" Ni -cad charger. Tx•Ing modals £52.50 Er £59.75 Charges most types Usual stocks of coax, plugs, etc., SAE with all enquiries. Lists 10 Bin 17p SAE Aerial Garde 50p. from AA to D size (inc. PP3) BRITANNIA STORES, LEESWOOD, Nr. MOLD, CLWYD CH7 4SD Publication Indoor and invisible aerials at the 14hr rate. £3.50 122.50 £1 60 pbp. Tel: Pontybodkin 846 (0352871 Callers welcome Tel 03986 215 62, Lavves Avenue, Newhaven G2DY M, Uplovvman, Tiverton. Shop open Mon, Wed, Thurs, Fri 9.30 5pm Sat 9.30 1pm E. Sussex BN9 9SB Closed Tuesday Devon.

580 RADIO CO M M UNICATION June 1981 IWOOD Et DOUGLAS I 9 HILLCREST, TADLEY BASINGSTOKE, HANTS RG26 6JB

NEW PRODUCTS As announced last month, we have introduced a number of new products for the radio amateur market. Full details of these are available in our new revised specification sheets. We also now have a full 'spare parts' list. All data will be sent on receipt on a large SAE. The main new projects available are:

70SY25B 70cms Synthesiser This long-awaited kit will make your 70FM05TR one of the most-versatile rigs available for 70cms. The kit consists of two pcb's which are designed to fit the same-size standard diecast as the 2M synthesiser. The logic board uses a special synthesiser integrated circuit to give 25kHz step simplex coverage of channel '00' to '99' ie 433• 000 to 435.475MHz. In addition you have repeater and reverse repeater splits up to channel '19'. The lower section of the band 1432 433MHz) is also covered in 25kHz steps. The board has an automatic crystal-controlled toneburst, out of lock inhibit and voltage stabiliser. Channel selection is in bcd for thumbwheels, MPU's and is of course fully compatible with the PROSCAN and DISP1/2. Interfac- ing is simple for customers already owning a WEED transceiver while new constructors will be offered dedicated new transmit hardware and the standard receiver. Prices and further details are now available, please ring.

144PA4/S RF Switched 2M Pre-A mplifier. Such has been the popularity of the 144PA3 that we have brought out an r.f, switched version for those people who just couldn't squeeze it into their commercial equipment. The board has one or two extra refinements and is very attractively priced. Again please ring for details.

Above is e brief listing of the current product range es lull kits. These cannot be sold and sold in the current rate. Please include 60p on your total order for post and packing. The kits include all component parts. We do have, however, many components that are hard ro get for the average pcb components except crystals unless stated otherwise. Suitable boxes and external hardware amateur which include 23cms pre-amp boards and devices IIVE645351, dreamt boxes, chip is not supplied in the kit but some suitable stock is held. Any kit purchased from the range will resistors (5 ffi and 100111. PTFE trim mers, Mallard thick.filrn amplifiers 10M335, 0M3611 etc. A be gladly serviced but a 12.50 cover charge would be appreciated on larger items. All items in kit large SAE 1A4 size) will bring you the latest lists and new projects. The range is constantly ex- form are usually ex-stock either with us or our rally agent J Birkett of Lincoln. Assembled items panding and it is worth giving a call if you have a simple query on TADLEY 1073561 5324 and unless stock will be 10 14 days from receipt of order, and will be tested and aligned to specifica- BASINGSTOKE 102561 24611 during evenings and weekends. The above prices include VAT at tion. London stockist is Amateur Radio Exchange in Ealing

A. WOOD, G4EEE M. P. TELK MAN, G8DCA

5 volt TRANSCEIVER POWER SUPPLIES D CI \NFIE 1 Short Circuit Proof 2 Foldback Current Limit 4 Amp £27.95 + £1.00 Carr. 3 Overvoltage Crowbar Protection 6 Amp £44.95 + £2.00 Carr. 12 AMP 4 Fused Output Protection 12 Amp £69.00 + £2.00 Carr. pà«., 5.pply 5 10 mV (Max.) Output Ripple 24 Amp £92.00 + £3.00 Carr. 13 -5v 6 Better Than 1% Regulation WARNING DO NOT 7 Thermal Overload Protection All Prices Include VAT. 8 Surge Rating "U, x Cont. Rating OBSTRUCT AIRFLOW Manufactured in UK Davtrend Limited Trade Inquiries 89, Kimbolton Road, STOP PRESS-VHF WAVEMETER Welcome PORTSMOUTH HANTS 135 450M Hz £24.95 (inc VAT Et carr) Access Cards Ports (0705) 816237 Incorporates switched-mode PSU, varicap tuning, Accepted He wlett-Packard Schottky diode detector.

G6CCC G4JKG RSGB PUBLICATIONS LIST ON PAGE 584 COALVILLE COM MUNICATIONS (Nr. junction 22 on M1 motorway)

FULL ZYCO M M RANGE TANGERINE A BRITISH COMPUTER- see it at our SHOP SUGIYA MA • 5800 HANDHELD • FM88 25 WATT Microtan 65 kit £79.35 10K Microsoft BASIC In For m £56.35 Microtan 65 assembled €90.85 X-Bug £19.95 MOBILE RIG • SCANNER RECEIVERS • ETC Tenon (min confg) kit £49.95 Tanramlmin. conlgl assemb (f17.40 Tenon (min. confgl assent £60.96 Tanram expanded assemb. £143.90 ALSO I and mobile 2m antennas. H89 CV's Antenna masts Expanded Tairas Kit £'103.16 Mini•Mother Board £11.50 from 3 foot to 18 foot Expanded Torten asemb. €114.66 Mini-Rack with Power supply £56.35 3;5 Amp power supplies £18.75 5/7 Amp power supplies £21.75 20-way Keypad €11.60 Keyboard case £3.00 Full ASCII keyboard f69.95 Manuals evadable separately E5.00 All accessories well priced, eg: PL259 at 47p each inc VAT! Micron £395.00 * FREE! 2m a antenna when you purchase a 2m rig! * TUSCAN from £271.00 + VAT: VIDEO GENIE £350.00 , VAT ACCESS 20 HOUR ORDER SERVICE POST EXTRA Many more accessories stocked BARCLAYCARD LARGE SELECTION OF BOOKS VAT INCL. COALVILLE COM MUNICATIONS (G4JKG) MICRO-PRINT LTD. 6 Ashby Road, Coalyille, Leics. 59 Church Stn3et. Stoke on Trent Tel: 107821 48348. SAE for details or ask for Alai Gray. Tel: 0530 38779/60396

RADIO COM MUNICATION June 1981 581 The Gables, 20 Baby Lane. Rampage, A. J. H. ELECTRONICS Rugby, Wanvickshire, CV22 511.1 TONNA (F9FT) Terms of Business: Cash with order. Mail order only, or Callers by appointment. Official orders accepted on a strict monthly basis. Handling Charge 50p. Minimum order £2.00. YOUR NUMBER ONE CHOICE Tel RUGBY daytime 76473, evening 71066. S.A.E. with enquiries. FOR 2m, 70 AND 23cm ANTENNAS Prices now include VAT. FULL MONEY-BACK GUARANTEE ON ALL ITEMS VHF RF. POWER TRANSISTORS: vMP 1 power )et £1.20. There are now two NEW antennas extending the TONNA range. For 144MHz a 13 element Freq. 3N204 dual gate mostet hie 24dB. nf2.5dB @ Portable-very easy to assemble and only 1-25 metres long when dismantled. Type Gaieldbl Output Volts MHz Price 200Mc £1.20. For 12136MHz a 21 element long yagi- which with its rugged construction is proving to give 2N6083 5.7 30w 12 175 £6.50 3SK51 1406731 dual gate mosfet He 20(1B excellent results. BLY87A 9 8 12 175 £4.00 nf2.2dB 200Mc 75p. length weight Telescopic Portable Meets SD1212-6 8.2 3 12 175 £2.50 BER84 this is the gate protected version of 1441V1Hz (MI Ileg) 18ft £16.76 lal 25ft. f24.94 tal BLW16A 10 1 12 175 £0.75 8E528/ ONLY 75p. 4 element 1.37 0-5 £14.20 tal AVANT) 'ON GLASS'MOBILE ANTENNAS PT4236A 10 lmin 12 175 £0.75 BIPOLARS: 81576 pnp VHF RF amp F11200 9 element fixed 3-33 1.9 £16.56 (el A real alternative-- receives and transmits PT4555 8 25 12 80 E4.00 MHz 20p. 2N4957 pop VHF/UHF RF amp nt 9 element portable 3-30 £18.44 la) through glass-no holes to drill-no magnet PT4556C 7 40 12 80 £5.00 only 31dB @ 1GHz 30p, ElF180 30p. BF166 9 element crossed 3-50 2-0 £28.75 (al to scratch paint-no clamps-takes only 2N5070 13 2.5(pepi 24 30 £5.00 VHF RF amp. 25p: BFY90 UHF RF amp, 95p: 13 element portable 4-50 2.5 E29.75 lal mirrutes to install, without tools-no ground 01152 VHF mixiosc, 15p. 16 ele ment fixed 6-40 4.4 £31.74 lal MDA800 8 amp 50 volt bridge rectifier OK for plane required -all electrical connections in. 12v PSU etc. 66p. 2 for £1.159. SILICON PIN DIODES series resistance only 435M Hz side car-complete with 1511 cable and con- 0-4 ohm @ 100 MHz designed for VHF band 19 element 3-20 1• 1 £19.00 (a) nector. 2m 3dEi. £16.42 tc) 70cm 3c10 27 30MHz RECEIVER PRE-A MPS 25dB switching etc BA.243 .IVHF), 20p: BA244 19 element crossed 3.30 1.8 £30.14 Ial £16.42 ICI 70cm 5dEl £17.79 1cl gain ivariable) 50ohm in Et out ready built PCB (UHF', 259. 21 element 4.60 2.6 £26.43 Ial ANDRE W HELIAX LDF4-50 COAXIAL £3.133 or in die cast box with BNC sockets VARICAP DIODES: - 21 element ATV 4-60 2.6 £26.43 lal CABLE. Attenuation per 1COft. 144MHz- 02.00. ITT210 useable to 1GHz 20p. 1296MHz 0.8dB. 435MHz - 1-6dB. 1296MHz-2.9dB. 10-7 MHz SSB CRYSTAL FILTERS Catho- 861105 for VHF/UHF tuner 50p matched 23 element" 1.64 0.9 E28.76 lb) £2.60 per metre la). deon type BP4133 lower sideband only, new set /4. BA111 20p. BB141 209. 4 x 23 element antennas - power 'N' Type connectors or Heliax LDF4-50 male and unused small size 38mm r 113mni r 15min AUDIO AMP IC. TBA1010 6 watt output ad- splitter --stacking frame £161.46 lal or female £9.00. 200 ohm imp: giveaway PRICE ONLY £4.00 ustable to 9 watt @ 14 volt single-in-line type 136MHz Satellite MICRO WAVE M ODULES - LUNAR - each; two for £7.00. and ideal for transceivers, receivers, record 9 element crossed 3.50 1.8 £35.67 la) ROTATORS - UR67 and UR43 COAXIAL 10- 7 MHz CRYSTAL FILTER for AM/FM 121 players, cassette players etc. BARGAIN OF Denotes 50f1 only All others 50f1 or 751-: ini CABLE ETC. KHz channel spacing .t 33 KHz @ 3db ITT type FER ONLY E1.36: two for £2.40. Supplied with pedance. PLEASE ADD CARRIAGE AS SHO WN lal 024DE/923L. imp. 910 ohm, ONLY £7.00. data sheet showing construction of stereo High quality Phasing Harness available. E3.50. lb) [1.60. Icl E1.40 MAINLAND ONLY. LOW PROFILE RELAY 12 volt coil. 2 pole amp. Full data sheet 119 pages). 209. change over contacts. P.C. Mounting, ideal BAG OF MIXED RESISTORS 1 watt carbon FOR FULL DETAILS OF OUR RANGE SEND 30p FOR OUR CATALOGUE for aerial change over 145MHz will handle up film preformed type, all with long leads plus

CVVO- ACCESS- VISA- •just telephone your card number. Al) pnces include VAT. Callers to 50 watts RF. NEW only £2.25. some 3 watt std types. 250 for £1.51). welcome, but by appointment only please. FETS Et MOSFETS:- FEEDTHROUGH CAPACITORS 1000pf E5565 f2N38191 "N" chan let Zap. 500v solder in hate 1in dia, 10 for 269. RANDA M ELECTRONICS, 2N4381 "P" chan let 28p. FERRITE RINGS 12mm dia. 10p ea. 12 Ccrebit Rood, Abingdon, Oxon OX14 1DEt. Tel: Abingdon (0235) 23080 (24 lime BF256LC "J" let 36p. FERRITE BEADS FX1115, 10 for 209. TIS88A -N" chan let 409. COMPONENT LIST 189 stamp.

BRAND NEW COMPONENTS BY RETURN OF POST VAT Inclusive. Postage 15p (Free over [51. List Free WRONG TIME? HIGH STABILITY RESISTORS 5% Tolerance }W carbon film El2 series 18 to 10M0. 1E24 series to 6M2I 1p MSF CLOCK is ALWAYS CORRECT - never gains or loses, SELF Metal Film 1W 6 PN tOR ta 2M2 Et 1W 10R to 10M0 El2 Series. 2p CAPACITORS SETTING at switch-on, 8 digits show Date, Hours, Minutes Mullard Subminiature Ceramic Plate capacitors 100V E12 Series and Seconds, larger digit Hours and Minutes for easy QUICK- 2% 1. 8pf to 47pf 3p. 2% 56pf to 333pf 4p. 10% 3 l to 4700pf 4p GLANCE time, can expand to Years, Months and Milliseconds, Plate Ceramic Capacitors 50V working for vertical mounting E12 Series from 22pf to 1000pf then E6 series 1k 5pf to 47k pf. 2P also parallel BCD output for computer etc and audio to record Miniature Polyester c.apecItors 250V working for vertical mounting and show time on playback, IDEAL for SKEDS, receives -01, .015, .022, •033, -047, .068 4p. 0.1 5p. 0-15 8 0-22 6p Rugby 60kHz atomic time signals, built-in antenna, 1000km 0-3380-47 8p. 0.681E3VI 11p. 1.0 15p. 1.5 209, 2-2 22p range, GET the RIGHT TIME, £54.80. ELECTROLYTICS Wire Ended (Mfds/Volts) -47150 Sp 10,50 6p 47 /16 6p 100/25 7p 220/25 8p 470/40 16p LOSING DX? Antenna Fault? Poor reports? Check FAST with an 1-0/50 5p 22/16 8p 47/25 Sp 100/53 8p 220/50 10p 1C,00/15 15p Antenna Noise Bridge, MEASURE resonance 1 150MHz and 2-2/50 59 22,25 Bp 47/50 6p 150/16 7p 470116 11p 1000/25 189 radiation resistance 2 1000 ohms, accurate ANS WERS direct- 4-7/50 6p 22/50 6p 100/16 7p 220/16 Bp 470/25 11p 1000140 359 TAG-ENDED CANS: 3300/25 2139. 4700/16 25p. 2500* 2500/63 £1.03. ly, no frequency pulling, GET MORE DX, £11.80. TANTALU M BEAD ELECTROLYTICS Subminiature vertical Mounting (Mfds/voltal RARE DX UNDER QR M? DIG it OUT with a Tunable Audio Notch 0-1/35 149 2-2/35 16p 15/16 20p 22(16 309 47,16 8)p Filter, between your receiver and speaker. BOOST your DX/ 0.22/35 149 4.7/6 14p 15125 359 22225 35p 69/3 30p 0.47/35 14p 4-7/25 169 22/6 209 33/10 30p 100/3 35p ORM ratio, 40dB notch, hear WEAK DX, £10.90. 1.0/35 14p 10225 29p 22/10 25p 47/6 3Dp 220:16 Et» MISSING DX? Make them HEAR YOU with a Speech Compressor, POLYSTYRENE Capacitors 63V working E12 Series Long Axial Wires between youf microphone and transmitter, BOOST your lOpf to 620pf 3p Up} to 10kpf Op 12kpf 5p TRANSISTORS POWER up to four times, 60dB agc, SOUND BIG, £9.90. BC107/8/9 10p BC547C/8Ci9C 7p BC212L Bp BFY50/51252 18p 8FX88 25p LINEAR OKAY? Check it with a Two Tone Oscillator, £11.70. 13C1472819 10p BC557C/58C29C 7p BC70 15p 2N2926 7p BSX19&20 15p 60kHZ RUGBY RECEIVER, as in MSF Clock, serial data and audio BC1571819 10p BCIEQL, 1841_ Bp 13F195.57 10p 2N3055 50p El 013586 25o 8 pin i.c.s. 741 18p 556 24p Holders 8 pin 9p 14 on 12p 16 pin 14p 28 gin 25p 40 Pin 4Olz outputs, can tune 50-70kHz and drive S meter, £15.70. DIODES (p.I.v.itimize Each fun-to-build kit includes all parts, printed circuit, case, postage 75/25mA 1N4148 29 800/1A 1N4006 Sp 400/3A 1N5404 14p 115215mA 0A91 6p etc, instructions, money back assurance so GET yours NO W. 100/1A 1N4002 4p 1000/1A 1N4007 7p 60/1 -5a SIMI 5p 100,•1A Bridge 25p 4C0/1A 1N4004 5p 1250/1A BY127 10p 30,45mA OA90 6p 302150mA AAY32 12p Zoner Diodes 624 series 400tnW. 3V3 to 33V 80. 1 watt 3V9 to 33V 12p CAMBRIDGE KITS LEDs 3 Et 5mm, Red 10p, .Green Et Yellow 14p. Grommets 3rnm 11p 5mr-n 2p Fuses 20mm glass 100mA to 5A. 0.8low 3p. A:- Surge 5p. Holders 5p. (p.c. or chassis) 45 (RT) Old School Lane, Milton, Cambridge The C.R. Supply Co. 127 Chesterfield Rd, Sheffield S8 ORN. Tel: 57771

PACKER COM MUNICATIONS you musRtehmayeemabVYAIVTEoMbeETITRI ANTENNAS & EQUIPMENT W M-2 for 2m 130-300MHz lincludes that vital 238MHz) .. C20.86 FOR THE RADIO AMATEUR W M-4 for 4m 65-150MHz ilor 4m, 6m, pmr and air band) 1720.e6 5)& 1)0 '15 W M-7 for 70cm 400-900MHz Ithe ONLY one we know of) £21.95 per wavemeter WATCH FOR FURTHER ANNOUNCEMENTS TVI. BC'. HIFII7 Probably the greatest problem facing Hams. Many of the filters available are useless in the U.K. as they are intended for the USA/Euro markets (VHF TV. 110/220V - not the UK UHF TV, 230/240V) Try ours, we think they are the best! KW COM MUNICATIONS LTD. VANGUARD WORKS, JENKINS DALE, ULF-8 UHF Hipass, a real stopper) £ 48 2m and 4m power splitters £14.25. ULF-4 For FM radio and VHF TV £3.50 XY Vert / horz rth/Lth switch CHATHAM, KENT ME4 5RT HF-DIN•A 5 pin DIN plug and socket (stereo) £3.95£21.46. for J•Beam XY aerial! HF -RCA Phone plugs and sockets Istereo/ f3.96 ( Match that entennal Many Jap rigs are for 52, not 5011. Coax can be "off", antennas are rarely perfect: get the most from your rig with our ATU's £19.45 PNP CO M M U NIC ATIO NS AT-146 for 2m 500W _1- S0239. BNC or N connectors. AT-4N for 4 and 6m - use for fixed or mobile . E19.65 PO WERBOX PO WER SUPPLIES RSGB "SELL YOUR GEAR HERE" SERVICE will be operating at most rallies this sum mer. Raise Protected against S'C the cash to buy the rig you always wanted. We sell on com mission or buy outright. AND OVER VOLTAGE "CO MP-CALL" Ring us for components or gear. We despatch promptly and include in- Model 49 12V 3A £35.75 PUBLICATIONS voice. Please pay promptly) Model 50 13-8V 5A £42.50 ACCESS now available Quote your card number over the phone. Add 15% VAT to order Model 51 12V 5A £42.50 ARE LISTED plus pErp. Send SAE for details on all our products P&P 12.50 BRIDGE END BARN, SOUTERGATE, CUMBRIA, 62, Lawns Avenue, Ne whaven ON PAGE 584

LA17 7TVV. 0229 89448 E. Sussex .BN9 9513

SR7 RADIO COM MUNICATION June 1981 CLASSIFIED ADVERTISEMENTS

(G3ZV11 GAREX Classified advertisements 20p per word, minimum £4.00 KOK 2025 2m SYNTHESISED TRANSCEIVER Box Number £1.00 extra to wordage or minimum. Full band coverage 25 or 12ikHz steps/ 10 channel memoryiscans memories or selected band portion/3W or 25W Tx %All the features you need at E225 inc VAT. Semi-display 1/8 page 21" x 33" (57 x 91mml £58.00 VHF FM MONITOR RECEIVERS 3/32 page lj" x 33" (42 x 91mm) £45.00 HE 12 POCKET SIZE 12 channel xtal controlled 4MHz bandwidth in range 130 175MHz. 1/16 page 1" x 3}" (26 x 91mm) £2.00 With diced and charger £57.96. Xtels extra. see below. Helical aerial £4.40. 1/32 page 1" x 1k" )26 x 43mm) £18.00 SOUNDAIR 008 PORTABLE SCANNER 8 channel xtal controlled. 140- 170MHz I6MHz Please write clearly. No responsibility accepted for errors. bandwidth). With nicad and charger £59. Xtals extra. Latest date for acceptance - 7 weeks before 1st of issue month. SR-9 top-selling monitor: 2m FM with 144 146MHz full coverage VFO plus 11 xtal controlled channels, ideal for fixed, ,M, and %P use. 12V DC operation £47.50.• All classified and semi-display advertisements MUST be prepaid. MARINE BAND version. 156-162MHz. same spec and price. Copy and remittance to: C. C. LINDSAY (cheques payable to RSGB). CRYSTALS FOR NR-56, SR-9. HF-12. SOUNDAIR 008 TM5613. SR-11 All 2m channels from 01145.001 to 32 1145-801 incl. at £2.46 ( 15p postl. Over 40 popular marine channels at 2 Leyburn Gardens, Croydon CRO 5NL. Tel: 01-686 5839. £2.815 1 i 169 post). Sae list. Members' Ads must be sent to the editor at Chelmsford. CRYSTALS FOR 28-5 MHz. 3rd overtone suit most Jap.,LISA 10m rigs 28• 5MHz Tx and ZI3•045MHz Rs HC181J (4.60 per pair. RESISTOR KITS new extended range at old price. 612 series 1011 to 1M. 61 values. 5% carbon film. General purpose ratings ¡W or ¡W (state which). Replenishments available. FOR SALE Starter pack, 5 ea value (3051 £3.10. Standard pack, 10 ea 1610) f5.65 Mixed pack 5 ea OW r- 3.W 16101 £5.56. Giant pack 25 ea (15251 (13.80. QSL CARDS printed to your own specifications on white gloss cards. SAE to Caswell NICAD RECHARGEABLES - physically as zinc carbon: (AA/U71 £1.30; CiU111 0.36; PP3 Press, 11 Barons Way, Woodhatch, Reigate, Surrey. £6.66. ANY 5 -•• less 10% ANY 10 - less 20%. LARGE STATION LOGBOOKS. Printed with your consign plus useful reference in- GAREX FM detector and squelch conversion ready assembled with lull fitting instruc- formation £2.25. Mobile Minilogs: 80p. Callsign Window Stickers: £1.50. Beauprint tions. Tailor made, easy fil design for AM Cambridge, replaces squelch board with minimum (G30Y11 Meltham Road, Hanley, Huddersfield. of other modifications £5.75 Transistor Vanguard IAM2511 version (modified squelchl £6.35 QSL CARDS. Quality printing on gloss or tinted cards. SAE for samples. Express PYE CAMBRIDGE SPARES (sae full list). Fix RF board 68-f38MHz Eb.96, 10 -7MHz I.F. £3.65. 2nd mixer 10-7MHz to 456kHz £3. 455kHz block filter 14kHz £9.40, ditto 255f-la £3. Printing Services, 28 Payne Avenue, Hove, Sussex. 455kHz AM I.F. £3.65. Audio bd (1.96. AM squelch 75p Many other RYE pans in stock.. TVI/AFI? Cure it with ferrite rings. 67p each incl postage. TMP ELECTRONICS, Britannia Stores, Leeswood, Nr Mold, Clwyd CH7 4RU. M AIN DISTRIBUTOR OF REVCO AERIALS Fi SPECIAL PRODUCTS AERIAL WIRE 14svvg hard drawn copper, 70' coils £5.50 140' £8.90 incl postage. PRICES INCLUDE UK POST Et PACKING Er 15% VAT. TMP ELECTRONICS, Britannia Stores, Leeswood, Nr Mold, Clwyd CH7 4RU. GAREX ELECTRONICS. 7 NORVIC ROAD, CRYSTALS MADE TO ORDER within six weeks, 4 -105MHz, wire or pins, £.90 8+!RCLAYCTARD MARSWORTH, THING. HERÍS HP23 41.,S. each inclusive. 70cm and 2m FM crystals from stock, £.95. SAE list. Hartley Crystals, MAIL ORDER ONLY Green Lane, Milford, Godalming, Surrey GU8 5BG. M al ME MORIES AND MICROPROCESSOR PERIPHERALS. Expanding your RAM or rAtu. Phone 0296 668684. Callers by appointment. extending a floppy? Parts available at competitive pricing. TOS. 57 Westmead, Wok- ing, Surrey GU12 3BS. 04862 20435. QSL CARDS Quality printing on coloured gloss cards, at competitive prices. SAE for samples S. M. Tatham, "Woodside", Orchard Way, Fontwell, Arundel, West THE INTERNATIONAL VHF-FM GUIDE SuRK EWITHsYsEex ME MORY. Straight paddle or Iambic, dot and dash store. High quality NEW FOR 1981 pcb E9.62; built and tested £44.95. SAE for details. REPEATER TIME OUT IN- DICATOR. Switchable 50, 80, 110 seconds. Rf sensing. No rig connection required. This unique guide has country by country maps and dotarle of VHF and UHF repeaters in £14.82 p&p 50p. GVB Electronics, 95 Old Worthing Road, East Preston, West Sussex. Europe, Scandinavia, Australasia and S. Africa and, in the Domestic edition, 48 pages of ex. tended coverage of individual UK VHF repeaters UK UHF repeaters are listed in channel 09062 70260. order. BUGGED? UNDER SURVEILLANCE? "The Bugging Game" is a unique, previously Reciprocal licensing requirements and addresses for 33 countries are given and will be in- restricted book describing modern countersurveillance and eavesdropping techniques. valuable to HE and VHF users. This guide is essential reading for the newcomer to repeaters A virtual encyclopaedia of "hidden knowledge" it tells ALL YOU NEED TO KNO W and for anyone planning operation abroad or through foreign repeaters. about professional and secret service methods! Part 1-Telephone Systems. Part The Domestic edition costs £1.75 UK postpaid (Overseas edition £1.25 postpaid to Europe) 2- Radio Er Microphone Systems. Part 3- Electronic Surveillance Et Counter- from: measures. 300 pages of unobtainable information! DON'T WAIT!.. .. this book could J. BALD WIN, G3UHK easily disappear from the market. Cyberscan International, 35 Dell Farm Road, Ruislip, Middlesex, HA4 7TX. Tel: (089561 73265. 41 Castle Drive, Maidenhead, Berks. SL6 6DB TS700S, all-mode, 144MHz, Xtals plus VFO, auto toneburst, reverse repeater, DFM, National Giro No 22 442 4009 etc. VGC. £299.00 ono. Newton Llantwit (0443) 202627. YAESU OWNERS. International Fox-Tango Club selected 6JS6C £.50 pair PP. FT News Letter $12 from USA. Sample 1980 omnibus book £3.25 PP. UK agent Mrs B. Leeming (XYL/G3LLL) 87 Durham Road, Wilpshire, Blackburn, 13131 9NH. Tel: 0254 INDEX TO ADVERTISERS 40762 eveneings. Callers appointment only, not Sundays please. Sae enquiries. ALU MINIUM QUAD SPIDERS boomless, £18.50 pair including p&p. Sae for details to G3ZHC. Tel: Walsall (09221 26659. Aero Er General Supplies 572 Mrcro• Print Ltd 581 DISCONE AERIAL 40-700MHz. Ideal for scanning receivers. Bargain at £7.94. Car- Aircom of Aborgavenny 580 Microwave Modules 510 AJH Electronics 582 Modular Electronics 558 riage extra. V-Tronix, 297 Herbert Avenue, Parkstone, Poole, Dorset. 0202 732856. Amateur Electronics 502/3 Mosley Electronics 558 Amateur Radio Exchange 506/7 Mutek Ltd 576 Amateur Radio Shop ...... 567. Ambit International . 574 Northern Communications 580 HOLIDAY ACCO M MODATION Amcomm Services 568,571 Fi 572 Arrow Electronics Ltd 573 Packer Communications 582 BOURNE MOUTH, DOLBADARN PRIVATE HOTEL, 8 'Grand Avenue. Partridge Electronics Ltd 580 Southbourne, BH6 3SU, between sea and shops. Residential licence, bedroom radio, J. Baldwin 583 Piper Communications . 578 call and tea making facilities. Excellent food. Dinner, bed and breakfast from £,00 Bedford Audiocomm 572 PM Electronics Services 566 J. Birkett 574 PNP Communications . .... 580 Et 582 daily. 0202 424.926. E. W. Et J. M. Batten IG3BKNI. Bredhurst Electronics 504/5 SUSSEX, NEAR WORTHING/BRIGHTON, bed and breakfast, 18th century flint Quarts Lab Marketing Ltd 570 cottage, car space, shack available, GEISUU. CITHR. Tel: Lancing 3102. Cambridge Kits 582 Catronics Ltd Cover II Radio Shack 5osi 9 Coalville Communications 581 Randam Electronics 582 CO Electronics 576 WA NTED CR Supply Co 582 SMC Ileeds1 Ltd 570 Datong Electronics 5,59 Sota Communications Systems Ltd .. 579 GOOD SECONDHAND EQUIP MENT ALWAYS WANTED. Corne to Amateur Davirend Limited 581 South Midlands Communications Ltd Radio Exchange for the best deal. 2 Northfield Road, Ealing, London W13. Tel: 01-579 511/156560 5311, Eurover Electronics Ltd 576 Spacemark Ltd 576 Siephons-Jarnes 577 EQUIP MENT W ANTED. Spot cash for good used amateur and marine radio Gares Electronics 583 Sussex Mobile Rally 570 equipment - or - your equipment sold at your price on small commission - no Gemini Communications 578 sale- no charge. Tel: Amcomm: 01-864 1166, 01-422 9585 GW M Radio Ltd 564 Telecom . 572 G2DYM Aerials 580 Telecommunications Accessories Ltd 564 Thanet Electronics 496/8 Heathlut 572 TMP Electronics Supplies 580 O. P. Hobbs Ltd 576 MISCELLA NEOUS Holdings Ltd 5E6 Uppington Tele -Radio Ltd 578 ILP Electronics Ltd 562 COURSES-RADIO AMATEURS EXA MINATION. City and Guilds. Pass this im- Ward Electronics 568 Interlace Quartz Devicas Ltd ...... 564 portant examination and obtain your 06 licence, with an RRC Home Study Course. Waters Er Stanton Electronics For details of this and other courses IGCE, Professional Examinations, etc) write or . 499/501 Er Cover .lIt Jaycee Electronics 578 Western Electronics (UK) Ltd 562 ,3 phone: The Rapid Results College, Dept JT1, Tuition House, London SW19 4DS. Tel: KW Radio 578 Et 582 W. H. Westlake 572 01.947 7272 (Careers Advisory Service) or for prospectus requests ring 01-946 1102 C. Wilson 576 (24hr Recordacall). LAR Modules Ltd 560 Wood Et Douglas 581. NEW AMATEUR RADIO/CO M MUNICATIONS CENTRE opening in Western Leeds Amateur Radio 561 Home Counties region requires agenciesidistributorships for any and all associated Lee Electronics 569 YelOSU Musen Co Ltd Cover IV H. Lemon Ltd 575 equipment and accessories. All replies answered immediately Box 184, RSGB, 2 Lowe Electronics 490/5 Zycomm Electronics Ltd 565 Leyburn Gardens, Croydon, CRO 5NL

RADIO CO M MUNICA TION June 1981 583 RSGB PUBLICATIONS OTHER PUBLICATIONS Title Publisher Price Books A Course in Radio Fundamentals • ARRL . £3.24 A Guide to Amateur Radio 118th edn, paperback) £3.07 ABCs of Antennas • Sams. £3.94 . A Guide to Amateur Radio 118th edn, hardback) £6.32 ABCs of Capacitors . • Sams. £4.44 Amateur Radio Awards (2nd edn) . . £3.41 ABCs of Fets . . • Sams. £4.04 Amateur Radio Techniques (7th edn) £6.16 ABCs of Integrated Circuits . Sams. £3.59 Amateur Radio Operating Manual . £4.96 Active- filter Cookbook . . . Sams. £12.69 Morse Code for Radio Amateurs . £1.31 All About Cubical Goad Antennas . RP) . E2.92 OSCAR-Amateur Radio Satellites . £4.50 Amateur Single Sideband . Ham Radio E4.58 RSGB Amateur Radio Call Book (1981 edn) £4.37 Amateur Television Handbook . BATC. £2.39 Radio Amateurs' Examination Manual 8th edn). £2.73 Amateur Tests and Measurements . Sams. £5.34 Radio Communication Handbook 15t h edn) Vol 1 £10.20 Antenna Anthology . . ARRL. £3.71 Radio Communication Handbook (5th edn) Vol 2 £9.06 ARRL Electronics Data Book . . ARRL. £3.58 Radio Data Reference Book 14th Kin) £5.02 Beam Antenna Handbook . . . API . . £4.22 Test Equipment for the Radio Amateur (2nd edn) £5.86 Beginners Handbook of Amateur Radio . Sarns. . £8.26 TV1Manuall2nd ed n1 ...... £1.95 Best of Oscar News . . . AMSAT-UK £1.64 VHF/UHF Manuall3rd edn) . . . £8.70 Better Short Wave Reception . . API . . £3.65 £4.28 World at their Fingertips ...... Care and Feeding of Power Grid Tubes . Varian . £2.98 CMOS Cookbook ...... Sams . £9.59 Logbooks Electronics for the Amateur . . . . . Sams . £7.53 Amateur Radio Logbook . . £2.86 PET Circuits ...... Sams . £4.46 Mobile Logbook . £1.14 PET Principles, Experiments and Projects . . Sams . £7.98 Receiving Station Logbook £2.68 FM and Repeaters for the Radio Amateur . . ARRL. £4.08 Frequency and its Measurement . . Sams . £3.59 Maps, charts and lists Hints and Kinks for the Radio Amateur . . ARRL. £3.32 Countries Listi HF Awards List . 34p IC Op-amp Cookbook . . . Sams. £11.82 Great Circle DX Map (wall) £2.12 IC Timer Cookbook . . . . Sams . £8.76 IARU Region 1 Beacon List . 32p Practical Antennas for the Radio Amateur . Scelbi. £8.02 IARU 0TH Locator Map of Europe (wall) £1.34 Radio Amateur Callbook-DX Listings (1981 edn) ARC) . £10.45 Oscar Map (in tube) . . . . . 56p Radio Amateur Cal/book-USA Listings (1981 edn) ARC) £10.95 0TH Locator Map of Western Europe (wall) . [1.34 Radio Frequency Interference . . . ARRL. £.09 0TH Locator Map of Europe (card for desk) 69p Radio Transmitter Principles and Projects . Sams . £6.28 UK Beacon List ...... 32p Radio Valve and Semiconductor Data Rook . Newnes £4.48 UK Repeater List . . . 32p RC Circuits Sams £4 51 World Prefix Map (wall) . £2.23 RTTY the Easy Way . . BARTG £1.14 Saga of the Vacuum Tube . . Sams . £9.09 Members' sundries Simple Low-cost Wire Antennas . . FiP1 . £3.16 RSGB hf contest log sheets (100) £2.28 Single Sideband for the Radio Amateur . ARRL. £3.84 RSGB leather belt . . £6.32 Solid State Basics . . . . ARRL. £4.85 RSGB teeshirt Ismall. mecJium. large) (new design) £3.41 Solid State Design for the Radio Amateur ARRL. £6.25 RSGB tie )blue, maroon, green) £3.34 Specialised Communication Techniques, ARRL £3.49 RSGB pennant . . . £2.47 The ARRL Antenna Book . . . ARRL. £4.30 RSGB station callsign plaque . £6.75 The Cheap Video Cookbook . . Sams. £5.47 RSGB deluxe lapel badge •. £3.82 The Complete Handbook of Slow Scan TV . . Tab . £5.76 Callsign lapel badge' . . . . £2.12 The Radio Amateurs Handbook (Paperback 1981 edn) ARRL. £8.56 Lapel badge (RSGB emblem, pin fitting) . . 75p The Radio Amateurs Handbook (Hardback 1981 edn) ARRL. £12.06 Members' headed notepaper (50 sheets) quarto. £1.07 The Radio Amateurs VHF Manual . . ARRL. £4.15 Members' headed notepaper (50 sheets) octavo. 76p The 8090A Bugbook . . Sams. £9.59 OSL card holders ...... £1.14 77L Cookbook . . . Sams £8.48 Radio Communication back issues (As available) 97p TV Typewriter Cookbook . Sams £8.70 Radio Communication bound volume, 1978 . £14.83 Understanding Amateur Radio ARAL. £4.32 Radio Communication bound volume, 1979 . . £13.55 Unique IC Op-amp Applications . Sams . £4.58 Radio Communication bound volume. 1980 (Parts 1 and 2) £14.53 Vertical Beam and Triangle Antennas . Sams . £5.01 Radio Communication Easibinder (old size) . £4.24 World Atlas . . . . . RACI . £1.91 'Delivery approximately five weeks World Radio and TV Handbook (1981 edn) Billboard £10.62 ZAPP- Impedance and power potential . £4 . 17 Car window stickers 80 Meter DXing . . . . . £3.03 "I'm on the air with amateur radio" (four co)ours) 84p 99 Ways to Improve your Short-wave Listening Sams . £4.44 "I'm monitoring 'Sane your (two colours) . 68p RSGB badge . . 40p

MORSE INSTRUCTION AIDS ORDERING INFORMATION Morse code cassette. Stage 1 . . . £3.85 G3HSC Rhythm method of morse tuition PRICES. These include postage, packing and VAT where applicable. For airmail Complete course (Two 3-speed (p records and one ep, plus books) £6.45 despatch, please ask for price before ordering. Goods are obtainable, less p & p, Beginner's course (One 3-speed 1p and one op plus book) . . £4.97 at RSGB headquarters between 9.30am and 5pm. Monday to Friday. • Beginner's 1p (0 15wpm) plus book ...... £4.29 Three-speed simulated PO test (7in dis epl . . . . £2.00 ME MBERSHIP DISCOUNT. RSGB members can obtain a 10 per cent dis- On all overseas orders for G3HSC course, including orders from Eire, count on the prices listed here at the time of ordering (excluding Ham Radio add £1.12 for additional packing and postage from supplier Magazine). To obtain the discount, deduct 10 per cent, calculated to the nearest penny, from the total value of the order (using the latest price list) and enclose a remittance for the balance. Also enclose a recent Radio Communication address label as proof of membership. MAGAZINE SUBSCRIPTIONS POSTAL TER MS. Cash with order. Stamps and book tokens cannot be OST (including ARRL membership). One year . £11.84 accepted. Cheques and postal orders should be crossed and made payable to Two years . . . .60 "Radio Society of Great Britain". Giro A/C No 533 5256. Please write your name Three years . . . £32.85 and address clearly on the order. Air mail, one year ...... £20.00 Send OST subscriptions to RSGB, 35 Doughty Street, London WC1N 2AE. ORDER FROM: RSGB Publications (Sales). Ham Radio Magazine (per annum) lincl air delivery) . . . £14.00 35 Doughty Street, London VVC1N 2AE Subscriptions and changes of address for Ham Radio Magazine should be sent to: Ham Radio Magazine (UK), PO Box 63, Harrow, Middx HA3 6HS. (Raynet supplies should be obtained from Mrs Balestrini, OTHR O3BPTi

584 RA DIO CO M MUNICA TIO N June 1981 WATERS & STANTON DUAL BAND FDK Better Quality ELECTRONICS ALL-MODE Lower Prices 18120 MAIN ROAD, HOCKLEY, ESSEX. Tel: (0702) 206835 FOR LESS THAN £500!

JUST THINK . . . 2m it 70cm . . FM/SSB/C W . DIGITAL READOUT.

AUTO MATIC REPEATER SHIFT . . . CROSS BAND OPERATION . . .

AUTO MATIC AERIAL SELECTION . . . AND ALL FOR . . .

£468.00! (MULTI-750E £299.00) MULTI 750E PLUS EXPANDER

144 146MHz Er 430 440MHz

SPECIFICATION

Frequency range: 144 146 (or 148) MHz 430 440MHz Frequency steps: 5kHz & 100Hz Operating modes: FM/USB/LSB/C W Supply requirements: 11-15 volts DC (13.8V nominal) Power consumption: 3 amps on transmit RF output: 10 Watts or 1 Watt Sensitivity SSB/C W: - 8dBp at 10dB S/N FM: -4dBp at 20dB N.O Audio output: More than 1.2 watts o 10% THD Size (each unit): 163W x 73H 260D in mm Note: all interconnecting leads are provided. 1111 1111

Its been a long time coming but with the Japanese home market amateur radio the press of a button. Aerial selection is carried out automatically so there are rul population of 770.000 it's been hard work to satisfy the demand! But now the cables to change when going from one band to another. In fact, it's even pos European version of the expander is at last on its way and by the time you read sible to transmit on one band and receive on another softy, no "listen through' this we hope to be well through the backlog of orders_ For those owners of the though! The correct repeater shift is automatically taken care of inside the Multi 750E, the EXPANDER unit is an absolute must and for those considering a M750E and because a very low level of drive is employed, there is no leakage on base or mobile unit that covers all modes on both 2m and 70cms then surely the 2 metres when operating on 70cms, Full coverage of 430- 440MHz is possible combination at E468 must be outstanding value at today's prices. with the EXPANDER at either 10W or 1W output and, of course, the dual VFO system can be used on both 2 metres and 70cms. Let's consider what the combination provides. Firstly, you have the luxury of do. Ing on 70cms what you have been able to do on 2 metres with your 750E. That In short, if you're a VHF/UHF man then the M750E and EXPANDER unit will means USB/LSB/C W/FM with full digital readout down to 100Hz with full provide a complete and comprehensive station for either fixed or mobile use signal strength and RF output metering. Secondly, band switching is done at Also coming shortly will be the matching AC power supply PS750.

UNBEATABLE PERFOR MANCE AT AN UNBEATABLE PRICE!

'12 M ONTH W ARR ANTY PARTS AND LAB OUR

SOLE UK DISTRIBUTORS SEE ORDER FOR M ON PAGE 501 • YAESU AIRMEN

F T 707 SOLID-STATE HF TRANSCEIVER "WAYFARER"

The FT707 "The Wayfarer" is an ultra-compact solid-state FT707 transceiver ideally suited for the home station or as a travelling com- * 80-10 metres (including 10, 18 and 24MHz bands) panion, providing performance previously proffered only by the * USB —LSB —CW W—C WN —AM (Tx and Rx operation) "Top liners". * All solid state — including "advanced" final amplifier The FT707 is THE radio of the eighties: 80-10m, including 30, 17 and * 100W PEP. 50% power output at 3:1 VSWR 12m—ail factory installed-100W output 110W 'S' model) 50% * Full "broad band" no tune output stage developed in 3:1 VSWR —Digital, bright LED's in mode sensitive * Excellent Rx. dynamic range, power transistor buffers counter plus analogue readout—Transceiver status at a glance from * Rx Schottky diode ring mixer module string LED and single displays-16 poles of crystal filtering provides * Local oscillator with ultra-low noise floor continuously adjustable IF bandwidth 2 -.4kHz to 300Hz (N.B. This is * Variable IF bandwidth— 16 crystal poles true "variable bandwidth" that minimises much of the adjacent * Bandwidths 6kHz" 2.4kHz-300Hz (600-350)Hz• 300Hz• channel interference not "IF shift")— Noise blanker of most advanc- * AGC; slow-fast switchable from the front panel ed design using local AGC loop—Schottky diode ring module, * VOX built-in and adjustable from the front panel power transistor buffers, ultra clean, low noise local oscillator are * Semi-break in with side tone for excellent CW combined to produce, size and price notwithstanding a most * Digital (100Hz) plus analogue frequency display remarkable receiver. * LED Level meter reads: S, PO and ALC * Convenient concentric AF/RF gain controls The FV707DM is an external digital VFO that uses an advanced twin * Indicators for: calibrator, fix, int/ext VFO loop PLL to provide 10Hz tuning steps with excellent spectral purity. * Receiver offset tuning (RIT-clarifier) control The addition of this 1" high package, with its 12 channels of * Advanced noise blanker with local loop AGC memory with Receiver independent tune and internal/external * 25kHz crystal calibrator feature (mid), up/down, fast/slow scanning, perfects the FT707 for mobile * Internal, xtal or external VFO control or contest use. FV707DM Illustrated below (L to R): The FP707 regulated power supply, the * 12 memory channels with RIT FT707 and the FC707 antenna coupler/switch/S WR meter on top of * Twin PLL system with 10Hz steps the FV707DM. * Scanning: up/down, fast/slow from mic or unit For further details of this exciting new system, please contact any FTV70) NEW! NEW! NEW! authorised sales outlet for a free colour brochure. Better still: see it * Matching transverter. Plug-in modules-6, 4, 2 or 70cm for yourself—try one out today!!! 'Optional E&OE

WORKING FOR OUR COMMON INTERESTS—at Yaesu Musen communication equipment is not a sideline but the only business. Over 130 licensed amateurs proudly produce the most diverse product line available, SSS, CVV, AM or FM for mobile, portable or base use.

SOUTH MIDLANDS YAESU MUSEN'S A MATEUR ELECTRONICS UK

CO M MUNICATIONS LTD ,,,Ag Erhe ONLY 508-514 ALU M ROCK ROAD SM HOUSE, OSBORNE ROAD AUTHORISED ALU M ROCK, TOTTON, SOUTHA MPTON SO4 4DN UK AGENTS rLg BIR MINGHA M 8